Many traffic lights charge when a car roll up intersection. How does the light sense the presence of car? Describe briefly.

Answers

Answer 1

Answer:

There are a few ways that traffic lights can sense the presence of a car. One way is by using inductive loops that are installed on the road. These loops detect changes in the magnetic field caused by a car passing over them. Another way is by using infrared sensors that detect the heat signature of a car.

Explanation:

Hope this helps!


Related Questions

If a car decreases in speed to a stop from an initial speed of 21 m/s in a period of 13 s, what is the average acceleration of the car? Show all work.

Answers

If a car decreases in speed to a stop from an initial speed of 21 m/s in a period of 13 s, the average acceleration is 1.62m/s².

How to calculate acceleration?

The acceleration of a moving body can be calculated by dividing the change in velocity (∆V) by the time taken. That is;

a = v - u/t

Where;

a = accelerationv = final velocityu = initial velocityt = time

According to this question, a car decreases in speed to a stop from an initial speed of 21 m/s in a period of 13 s. The average acceleration is as follows:

acceleration = 21 - 0/13

acceleration = 1.62m/s²

Therefore, if a car decreases in speed to a stop from an initial speed of 21 m/s in a period of 13 s, the average acceleration is 1.62m/s².

Learn more about acceleration at: https://brainly.com/question/12550364

#SPJ1

An automobile and train move together along parallel paths at 28.8 m/s. The automobile then undergoes a uniform acceleration of −4 m/s^2 because of a red light and comes to rest. It remains at rest for 63.8 s, then accelerates back to a speed of 28.8 m/s at a rate of 1.58 m/s^2.

How far behind the train is the automobile
when it reaches the speed of 28.8 m/s, assuming that the train speed has remained at 28.8 m/s?
Answer in units of m.

Answers

2197 m far behind the train is the automobile when it reaches the speed of 28.8 m/s, assuming that the train speed has remained at 28.8 m/s

s₁=v²/2a₁=28.8²/2•4=103.7 m.

Automobile:

s=s₁+s₃=103.7+262.5=366.2

t= t₁+t₂+t₃=7.2+63.8+18.2 = 89 s.

Train:

S=v •t=28.8•89=25 63.

Δs=S-s =2563.2-366.2=2197 m

In physics, what does kinematics mean?

The study of motion in a system of bodies is called kinematics, which does not directly take into account the forces or potential fields influencing the motion. In other terms, kinematics investigates the distribution of momentum and energy among interacting entities.

Understanding the causes of various motions of an item, such as rotational motion in which the object receives force or torque, is the main goal of kinetics. The definition of concepts like acceleration, velocity, and location of objects is provided by kinematics.

learn more about kinematics refer

https://brainly.com/question/24486060

#SPJ9

(a) When an object's acceleration vector points in the same direction as its velocity, which of the following is true?
A. the object speeds up without turning.
B. the object slows down without turning.
C. the object turns without changing speed.

Answers

A. When an object's acceleration vector points in the same direction as its velocity, the object speeds up without turning.

What is acceleration vector?

The average acceleration vector is defined as the rate at which the velocity changes with time.

When an object is slowing down, the acceleration of the object is in the opposite direction as the velocity.

Also, when an object is speeding up, the acceleration of the object is in the same direction as the velocity.

Thus, when an object's acceleration vector points in the same direction as its velocity, the object speeds up without turning.

Learn more about acceleration vector here: https://brainly.com/question/14300387

#SPJ1

After an experiment, research participants are told its purpose and about any deception they may have experienced. This is called
a. replication.
b. the double-blind procedure.
c. debriefing.
d. informed consent.

Answers

After an experiment, research participants are told its purpose and about any deception they may have experienced. This is called debriefing. So, the correct option is (c).

Debriefing is the act of reporting on a mission, project, or the data gleaned from it. After an activity or event, a structured procedure examines the actions performed.Debriefing is a methodical learning procedure created to help plans continually improve as they are being carried out.

Debriefing can be used as an example during an experiment when the researchers required to use some type of deception for the purpose of the study.

Debriefing has its roots in the military as a technique to learn quickly in rapidly changing situations and to correct mistakes or changes on the field. In this instance, the researchers would describe their reasoning for deception and the goal of the study during the debriefing session.

Learn more about debriefing here:

https://brainly.com/question/28212765

#SPJ9

100 m/s northwest express what type movement

Answers

Answer:

There is more to motion than distance and displacement. Questions such as, “How long does a foot race take?” and “What was the runner’s speed?” cannot be answered without an understanding of other concepts. In this section we will look at time, speed, and velocity to expand our understanding of motion.

A description of how fast or slow an object moves is its speed. Speed is the rate at which an object changes its location. Like distance, speed is a scalar because it has a magnitude but not a direction. Because speed is a rate, it depends on the time interval of motion. You can calculate the elapsed time or the change in time, Δt, of motion as the difference between the ending time and the beginning time

The SI unit of time is the second (s), and the SI unit of speed is meters per second (m/s), but sometimes kilometers per hour (km/h), miles per hour (mph) or other units of speed are used.

When you describe an object's speed, you often describe the average over a time period. Average speed, vavg, is the distance traveled divided by the time during which the motion occurs.

vavg=

distance

time

You can, of course, rearrange the equation to solve for either distance or time

time =

distance

vavg

.

distance = vavg × time

Suppose, for example, a car travels 150 kilometers in 3.2 hours. Its average speed for the trip is

vavg =

distance

time

=

150 km

3.2 h

47 km/h.

A car's speed would likely increase and decrease many times over a 3.2 hour trip. Its speed at a specific instant in time, however, is its instantaneous speed. A car's speedometer describes its instantaneous speed.

Explanation:

Limestone bedrock can weather and dissolve. The erosion of the limestone can result in all the following landforms except

Caverns
Ridges
Sinkholes
Underground waterways

Answers

The erosion of the limestone can result in all the following landforms except ridges.

weather -

Climate is  the average weather condition of a place. It refers to the way in which the weather of a place stays over a given period of time. The weather condition of a place is known to change from time to time.

Limestone - It is type of  minerals that could occur at a given place.

The presence of the limestone in a place is able to change or alter the landform or the arrangement of the land in a given area.

Some of these changes are very much significant and can be easily observed in an area where there is a Limestone bedrock. Landforms could be a characteristic of a place and we know that it could be used to identify a given area.

The erosion of the limestone can result in all the following landforms except ridges.

To know  more about Limestone

https://brainly.com/question/14025896

#SPJ1

Answer:

B. Ridges

Explanation:

Proof shown below

Which describes the greatest displacement?
A. Walking 3 m east, then 3 m north, then 3 m west
B. Walking 3 m east, then 3 m south, then 3 m east

Answers

b , you are 6m away from where you started whereas answer a you are only 3m from where you started!

How does the mass of an object affect the potential and kinetic energy?

Answers

Answer:

The more mass the more kinetic energy it has

Explanation:

like a plastic ball and a metal one the metal one will fall faster.

hope this helps

Stress that has a beneficial effect on us is called

Answers

Answer:

a positive form of stress having a beneficial effect on health, motivation, performance, and emotional well-being … during positive stress ("eustress"), such as a promotion or vacation, feel-good chemicals called endorphins are released

Explanation:

that is the answer

The speed of sound is 344 m/s. You have built a really fantastic car that can really go fast. If the car can accelerate at 22.4 m/s how much time till you reach the speed of sound? How many kilometers will you travel before you reach that speed?

Answers

Answer:

About 15 seconds,.344 kilo

Explanation:

Answer:

15.36 [sec]; 2.64143 [km].

Explanation:

all the details are in the attachment, note, the suggested solution consists of two parts: formula and solution.

Baseball A and B have masses 250g and 300g respectively.
Both are hit by the same amount of force equal to 100 N(Newton).
Which of the two baseballs has greater acceleration?

Answers

The baseball with the greater acceleration is baseball A

Relationship between force and acceleration

Force and acceleration are related according to the following formula:

Force (F) = mass (m) × acceleration (a)

F = ma

How to determine the acceleration of baseball AForce (F) = 100 NMass of A (m) = 250 g = 250 / 100 = 0.25 KgAcceleration of A (a) =?

F = ma

Divide both sides by m

a = F / m

a = 100 / 0.25

Acceleration of A = 400 m/s²

How to determine the acceleration of baseball BForce (F) = 100 NMass of A (m) = 300 g = 300 / 100 = 0.3 KgAcceleration of B (a) =?

F = ma

Divide both sides by m

a = F / m

a = 100 / 0.3

Acceleration of B = 333.33 m/s²

From the above calculations, we obtained:

Acceleration of A = 400 m/s²Acceleration of B = 333.33 m/s²

Thus, baseball A has the greater acceleration

Learn more about Force and acceleration:

https://brainly.com/question/1046166

#SPJ1

Question 3: Vectors (13 points)
a. Draw the two vectors below added together. Then draw the sum of the two
vectors. (1 point)

Answers

The sum of the vectors is shown in the image attached to this answer.

What is a vector?

A vector quantity is a quantity that has both magnitude and direction. In effect, as we try to obtain the combination of the vector we also have to consider the direction. The vectors are often shown  by the use of a bold face or by the use of an arrow over the sign of the vector.

Now looking at this vectors, we know that the sum of the vectors can only be obtained geometrically but the arrows of the vectors must have to point in the appropriate directions for the correct  sum to be obtained.

Thus the sum of the vectors is shown in the image attached to this answer.

Learn more about vector:https://brainly.com/question/13322477

#SPJ1

How far from a 1.00 μC point charge will the potential be 200 V?

Answers

The charge will the potential be 200 V = 2.23 x 10⁸ C

Given:

r = 1.00 μC

v = 200V

K = 8.988 x 10⁹ NM²/C²

Charge, also known as electric charge, electrical charge, or electrostatic charge, is a property of a unit of matter that shows how many more or fewer electrons than protons it possesses. It is represented by the symbol q.

A body that feels a force in an electric field has a property called charge. It is more useful to speak of bundles of electrons because individual electrons are so tiny and have little impact.

The formula for find how far from a 1.00 μC point charge will the potential be 200V.

V = kq / r

q = rV/ K

Charge = (1.00 x 10⁻³m)(200)/ 8.988 x 10⁹ NM²/C²

            = 2.23 x 10⁸ C

So, The charge will the potential be 200 V = 2.23 x 10⁸ C

Learn more about charge problem here:

https://brainly.com/question/18102056

#SPJ9

Is amalee wearing purple?

Answers

Answer:

yes.

Explanation:

Answer:

yes

Explanation:i am THE Amalee

Limestone bedrock can weather and dissolve. The erosion of the limestone can result in all the following landforms except

Caverns
Ridges
Sinkholes
Underground waterways

Answers

The erosion of limestone bedrock can result in the formation of all the following landforms except ridges.

Limestone is a type of sedimentary rock that is primarily composed of the mineral calcite (calcium carbonate, CaCO₃). It accounts for around ten percent of the total volume of all sedimentary rocks. This rock is distinguished by the fact that its principal constituent, calcite, is primarily formed by shell-producing and coral-building living organisms. The action of acidic water on limestone deposits has created numerous caverns, gorges, sinkholes, and other natural landforms.

Whereas, a ridge, often known as a mountain ridge, is a geographical feature composed of a series of mountains or hills that form a continuously raised crest over a long distance.

Therefore, the erosion of limestone bedrock can result in the formation of caverns, sinkholes, and underground waterways except for ridges.

Read more about Limestone erosion:

https://brainly.com/question/28678084

#SPJ1

Two students perform an experiment with soccer balls. They kick bro soccer balls so that they collide. They measure the total momentum of the two soccer balls before and after
the collision Which statement explains why the total momentum of the soccer balls before and after the collision may not be the same? (1 point)
O The soccer balls each have a different momentum after the collision than before the collision
O The soccer bails exert forces on each other when they collide
O The system does not have any extemal forces
O The system has external forces, such as thiction and air resistance, acting on it

Answers

D) The system has external forces, such as friction and air resistance, acting on it.

According to Newton's first law, a change in motion is brought about by a net external force. External forces are forces that originate outside of an object or system and operate on it. Internal forces are generated within the studied system and do not result in acceleration. As a result, while analyzing an object's motion, we only take into account the exterior forces that cause it to accelerate, ignoring the interior forces.

The applied force, normal force, tension force, friction force, and air resistance force are examples of external forces. The internal forces, however, also include gravitational, magnetic, electric, and spring forces. A greater acceleration results from a greater net external force. The system's acceleration would thus be inversely proportional to the system's net external force.

To learn more about external forces please visit-
https://brainly.com/question/16186958
#SPJ9

how to find potential energy

Answers

Answer:

The formula for potential energy depends on the force acting on the two objects.

A car is behind a truck going 25 m/s on the highway the car driver looks for an opportunity to pass guessing that his car can accelerate at 1 m/s squared he gauge that he has to cover the 20 m length of the truck +10 m to clear room at the rear of the truck and 10 m more at the front of the truck in the upcoming lane he sees a car approaching probably also traveling at 25 mi./s he has made the car is about 4.0×10 to the 2nd m away should he attempt to pass

Answers

The car will travel only distance of 25.92 m.In order to overtake it needs to travel 40m. So don't attempt to pass the truck.

Vehicle speed is 25 m/s.

40m is the distance the automobile must go to pass the truck.Distance between the car approaching from the opposite direction and the passing location is 400-40, or 360 meters.

Time allowed for a car to pass a truck of 20 meters in length is equal to the distance between the automobile coming from the other direction and the relative speed of the two cars.

Time equals 360/50, or 7.2 seconds.

Let's assume that the truck is going at the same rate as the car.

The expression "distance traveled by car in comparison to truck"

S is the distance traveled, u is the initial velocity, an is the acceleration, and t is the amount of time spent, where S = ut +[tex]\frac{1}{2}at^{2}[/tex]

Here, u = 0, t = 7.2 s, and a = 1 m/[tex]s^{2}[/tex]

hence, the distance driven in 7.2 seconds

So,     S = 0+ 25.92 = 25.92 m

So car will travel only travel 25.92 m

In order to overtake it needs to travel 40m. So don't attempt to pass the truck.

Learn more about distance here:

https://brainly.com/question/23821700

#SPJ9


The distance between the sun and the Earth is about 1.5 x 10¹1 m. Express
this distance in terameters (Tm) and kilometers.

Answers

Answer: 0.15 Tm, 150000000 km

Explanation:

150,000,000,000m  to km=150000000 km (divide by 1000)

150,000,000,000m  to Tm=0.15 Tm

What is the relationship between potential energy and
gravity?

A. Gravity has nothing to do with potential energy

B. Potential energy is the same thing as gravity

C. Objects in motion can be stopped by gravity

D. Objects have the potential to fall due to gravity

Answers

Answer:

D

Explanation:

the amount of potential energy is dependents on the weight and the hight and gravitational energy being forced onto a object.

3. Complete the following sentences:

a. "The slope of a linear position graph tells us the _________________________ of the object."


b. "The slope of a linear velocity graph tells us the Acceleration of the object."


c. "For an object moving at a constant speed, we would expect to see a position graph with a ___________________ shape and a velocity graph with a ___________________ shape."


d. "For an object moving at a constant acceleration, we would expect to see a position graph with a ___________________ shape and a velocity graph with a ___________________ shape."

Answers

a.velocity

c.linear - horizontal

d.parabolic - linear

The slope of a linear position graph tells the velocity of the object, for an object which is moving at a constant speed the position graph with linear shape, and the velocity graph with horizontal shape, and for an object which is moving at a constant acceleration the position graph will be the in parabolic shape and velocity graph is of linear shape.

What is Acceleration?

The rate of change in an object's velocity with respect to time is known as acceleration in mechanics. The vector quantity of accelerations. The direction of the net force that is acting on an object determines its acceleration.

Since acceleration has both a magnitude and a direction, it is a vector quantity. Velocity is a vector quantity as well. The definition of acceleration is the change in velocity vector over a time interval divided by the time interval.

There are several types of acceleration :

Uniform AccelerationNon-Uniform AccelerationAverage Acceleration

To get more information about Acceleration :

https://brainly.com/question/3046924

#SPJ2

Question 1 of 20
Calculate: (9 x 10^8) divided (3 x 10^4) =
A. 6 x 10^4
B. 3 x 10^4
C. 3 x 10^4
D. 6 x 10^2

Answers

the answer is 30000!

The graph shows the acceleration of a racehorse taking off from a starting gate. By how much did the horse's speed increase between 4 seconds and 6 seconds?

Answers

The speed of the racehorse increases by 27m/s.

Speed, expressed in terms of meters per second, is the rate at which an object's location changes. An item moves one meter in one second, for instance, if it starts at the origin and moves three meters in three seconds. A simple division of time by distance yields the equation for speed. To calculate speed, divide the distance traveled (say, 3 meters) by the passing time (say, three seconds) (one meter per second).

Speed is measured as distance moved over time.

Speed =  Distance/Time

We can also use these symbols:

Speed =  Δs/Δt

Speed is commonly measured in meters per second (m/s or m s-1), or kilometers per hour (km/h or km h-1)

To learn more about speed please visit-
https://brainly.com/question/7359669
#SPJ9

Find the energy-consumption rate for five electrical devices you use every day. This value-in watts-is generally listed somewhere on the device or its power adapter, if it has one





For the devices identified in Question 3, estimate t total time you use each device in a day, and use th quantity, along with the device's energy-consumpto rate, to estimate the total energy each uses in a day

Answers

The amount of energy used is known as energy consumption.

Find the energy-consumption rate for five electrical devices you use every day.

The following is the power consumption formula or energy consumption formula: E = P*(t/1000); where E is energy expressed in Joules or kilowatt-hours (kWh), P is power expressed in watts, and t is the duration of the consumption of the power or energy.

A lot of electricity is used by electrical appliances. Those that produce heat or have moving parts consume a lot more energy than those that do the same for light or sound.

A higher-wattage appliance actually uses less electricity overall than a lower-wattage one, because it is properly made and completes its task more quickly.

The following are some of the commonly used electrical devices in a daily household.

LCD TV consumes 120W.Washing machine consumes 2100W.Fridge consumes 150W.Desktop computer consumes 140W.Microwave  consumes 1000W.

To know more about Energy Consumption, click on the link below:

https://brainly.com/question/13976868

#SPJ9

Surviving a Large Deceleration On July 13, 1977, while on a test drive at Britain's Silverstone racetrack, the throttle on David Purley's car stuck wide open. The resulting crash subjected Purley to the greatest "g-force" ever survived by a human - he decelerated from 173 km/h to zero in a distance of only about 0.66 m.

Calculate the magnitude of the acceleration experienced by Purley (assuming it to be constant), and express your answer in units of the acceleration of gravity, g=9.81m/s2 .

Answers

The magnitude of the acceleration experienced by Purley is -1749.82 m/s²

How to convert 173 Km/h to m/s

We'll begin by converting 173 Km/h to m/s. This can be obtained as follow:

3.6 Km/h = 1 m/s

Therefore,

173 Km/h = (173 Km/h × 1 m/s) / 3.6 Km/h

173 Km/h = 48.06 m/s

How to determine the acceleration

The following data were obtained from the question:

Initial velocity (u) = 48.06 m/sFinal velocity (v) = 0 m/sDistance (s) = 0.66 mAcceleration (a) = ?

The acceleration can be obtained as follow:

v² = u² + 2as

0² = 48.06² + (2 × a × 0.66)

0 = 2309.7636 + 1.32a

Collect like terms

1.32a = 0 - 2309.7636

1.32a = -2309.7636

Divide both sides by 1.32

a = -2309.7636 / 1.32

a = -1749.82 m/s²

Learn more about velocity:

https://brainly.com/question/3411682

Learn more about acceleration:

https://brainly.com/question/491732

#SPJ1

Mention 2 everyday applications each of conduction, convection and radiation​

Answers

Answer:

Conduction: Touching a stove and being burned. Ice cooling down your hand. .

Explanation:

What equation is used to determine the total power consumption in a series circuit?

Answers

Answer:

PN=P1+P2+P3.......................PN

The flux density between two plates separated by mica of relative permittivity 5 is 2 microColumbs per square meter. Find the voltage gradient between the plates.​

Answers

According to the given statement The voltage gradient between the plates is ​45.2kV/m

What is high voltage gradient?

The Volt/meter (V/m) unit of measure for potential gradient is standard. Take a look at the graph between the potential gradient and distance. The potential gradient is strong when the object is close to or at a low distance from the high voltage wire; as you increase the distance, the gradient reduces.

Briefing:

Flux Density

D = 2μC/m²

D =2×10⁻⁶ C/m²

ε[tex]_0[/tex] = 8.85 × 10⁻¹² F/m

ε[tex]_r[/tex] = 5

D/E = ε[tex]_0[/tex]ε[tex]_r[/tex]   hence voltage gradient

E = D/ε[tex]_0[/tex]ε[tex]_r[/tex]

= [tex]\frac{2 \times 10^{-6}}{8.85 \times 10^{-12} \times 5} \mathrm{~V} / \mathrm{m}[/tex]

= 45.2kV/m

The voltage gradient between the plates is ​45.2kV/m

To know more about Voltage Gradient visit:

https://brainly.com/question/17373203

#SPJ9

Can someone explain the question below by giving me an example with numbers? I'm confused about how to approach the question.

The diagram of the problem is in the picture attached and the question is: What is the magnitude of static frictional force that must act on box 2 in terms of F, the magnitude of F, m1, m2, µk and g?

Answers

Answer: kfhfjffhfjfvfh.

Explanation: hfhvfffhfhf.

A fighter hits a punching bag and brings it from rest up to a speed of 40 m/s in 0.08 s. What is the force of impact on the punching bag if its mass is 100 kg?

Answers

if a fighter hits a punching bag and brings it from rest up to a speed of 40 m/s in 0.08 s, Then the force of impact on the punching bag if its mass is 100 kg would be 50000 Newtons,

What is Newton's second law?

Newton's Second Law states that The resultant force acting on an object is proportional to the rate of change of momentum.

The impact of the force on the punching bag = momentum/time

                                                                           =100×40 / 0.08

                                                                           =5000 Newtons

Thus, the force of impact on the punching bag would be 50000 Newtons.

Learn more about Newton's second law from here, refer to the link;

brainly.com/question/13447525

#SPJ1

Other Questions
denzel is one of 50,000 people defrauded of $40 in an advertising scam. denzel's best course of action to recover his money is to Scientific evidence indicates that the CO added to the air by the burning of wood and fossil fuels is contributing to global warming, a rise in global temperature. Tropical rain forests are estimated to be responsible for approximately 20% of global photosynthesis, yet the consumption of large amounts of CO by living trees is thought to make little or no net contribution to reduction of global warming. Why might this be? (Hint: What processes in both living and dead trees produce CO ?) owner investments cause a(n) (increase/decrease) in equity and are entered directly in owner's (capital/withdrawals/revenue).\ A mother wants to invest $13000 for her children's education. She invests a portion ofthe money in a bank certificate of deposit (CD account) which earns 4% and theremainder in a savings bond that earns 7%. If the total interest earned after one year is$780, how much money was invested at each rate? Think about the events that have occurred in Part of "The Monkey's Paw." Select one event that creates tension inthe story. Write a few sentences that describe how that specific event creates tension. has the beneficiary ever been part of any organization, association, fund, foundation, party, society, club, or group anywhere in the world? A seven-digit number has a 9 in the thousands place, a 2 in thehundred thousands place, a 6 in the greatest place-value position, a 4in the ten thousands place, a 1 in the tens place, a 5 in the leastplace-value position, and a 7 in the hundreds place. What is thenumber? A Canadian company with a registered HST number receives an invoice from asupplier for $1,000 worth of goods. There is $130 of HST charged on the invoice. Towhich of the following general ledger accounts will the $130 of HST be coded?hHST Tax (Liability/Asset)Cost of Goods Sold (Expense)Sales (Income)Tax Expense (Expense)ANSWER COMPLETESKIP THIS QUESTIONExit What is the missing factor in this factor tree? When a Personal Auto policy includes Other Than Collision coverage, physical damage coverage will cover all of the following losses, except: what may happen to eli and his father? check all that apply.they will pay for elis and daves care.they will not have to pay any costs because the accident was not daves fault.eli will be covered by daves family car insurance policy.they w what was the treaty of tordesillas ? Did the pope have any regard for the native populations of the American? Hi everyone, I am french and I have problems with my english homework. Could someone help me please for Q5 and Q6 ? It is a grammatical analysis. Any help will be appreciated If a person experiences mood states that vacillate between depression and mania, they may have ________. Find the measure of the exterior angle.(Click document to see image.) When clorox uses the good housekeeping seal for its fresh step cat litter, its strategy is to reduce a consumer's __________ and encourage purchases. Identify the number of solutions of the system Of a linear equation. X+3y-z=2. X+y-z=0 3x+zy_3z=-1 which is considered an appropriate outcome when planning care for an inpatient client diagnosed with somatic disorder? Geometric mean of 4 and 64 Simplify(3y)^2 x y^-1