Answer: 2
Explanation:
:}
A police officer standing at the side of the road uses a radar emitting frequency of 24.15 GHz. A car is going away from the officer at a speed of 50mph. What will be the difference in frequency of the beam reflected by the car received back by the radar?
a. 4.0 kHz (lower frequency)
b. 1.8 kHz (higher frequency)
c. 4.0 kHz (higher frequency)
d. 1.8 kHz (lower frequency)
Answer:
The correct answer is C
Explanation:
From the question we are told that
The frequency of the radar is [tex]f = 24.15 \ GHz = 24.15 *10^{9} \ Hz[/tex]
The speed of the car is [tex]v = 50 mph = \frac{50}{2.237} = 22.35 \ m/s[/tex]
Generally the difference frequency reflected by the car and the frequency which the radar receives back is mathematically represented as
[tex]\Delta f = \frac{f * 2 * v }{ c }[/tex]
Here c is the speed of light with value [tex]c = 3.0 *10^{8} \ m/s[/tex]
=> [tex]\Delta f= \frac{2 * 24.15 *10^{9} * 22.35}{ 3.0*10^{8}}[/tex]
=> [tex]\Delta f = 4000 \ Hz[/tex]
=> [tex]\Delta f = 4.0 \ kHz[/tex]
Given that the value is positive then it a higher frequency
what is mean by combination reaction ?
[tex] \underline{\purple{\large \sf Combination \: reaction :-}} [/tex]
Those reaction in which two or more substances combine to form a one new substance are called Combination reaction
In this reaction, We can add :
Two or more elements can combine to form a compound.Two or more compounds can combine to from a one new compound.An element and a compound can combine to form a new compound.[tex] \underline{\green{\large \sf For\: example :}} [/tex]
[tex] \sf 2H_{2} + O_{2} \: \underrightarrow{Combination} \: 2H_{2}o[/tex]
In this, Hydrogen is an element and Oxygen is another element. Both are combined to form compound 'Hydrogen oxide'. Hydrogen oxide is commonly known as water.
The compound formed from the elements calcium and chlorine is known as
Answer:
calcium chloride
Explanation:
an inorganic compound,a salt with the chemical formula CaCl2
20 pts.
Which of the following statements is true?
O Electromagnets use electrlcity and magnets.
O Magnetic fields are strongest around the poles of a magnet.
O The south pole of a magnet will repel the south pole of another magnet.
O all of the above
Answer:
all are true so d is right
Explanation:
Electromagnets use electrlcity and magnets is true.
Magnetic fields are strongest around the poles of a magnet is true.
The south pole of a magnet will repel the south pole of another magnet is true
and since all of them is true the answer is d all of the above
What electromagnetic wave is a is a TV remtoe
Answer:
infared radiation
Explanation:
PHYSICS! HELP ME PLEASE ASAP!
1.) If an ambulance passes you while you're walking your dog, a change in pitch is ____?
A.) not perceived by either the pedestrian or you
B.) perceived by the you
C.) perceived by the driver
2.) In the star wars movies, the soundtrack is very important. musicians and sound technicians spend weeks perfecting the noise of the light sabers, lasers, tie fighters and explosions. in real life, there would be no sound at all in space. Why?
A.) mechanical waves require a medium to travel
B.) sound is an electromagnetic wave
C.) mechanical waves do not require a medium to travel
D.) sound is a product of vibration
3.) what is a compression?
A.) region of zero pressure in a medium caused by a wave passing
B.)region of a high altitude in a medium caused by a passing wave
C.) region of a high pressure in a medium cause by a passing wave
D.) region of low pressure in a medium caused by a passing wave
Answer:
1B, 2B and 3C hope this helps
Explanation:
*
If a rock falls for 3 seconds off of a bridge, how far will the rock fall?
-30 m
-45m
-60m
-75m
Through what angle in degrees does a 33 rpm record turn in 0.32 s?
63°
35°
46°
74°
Answer:
1 rev = 2(pi) rad pi(rad) = 180 degrees
so 33 rev/min * 1 min/60s * (2*pi)rad/1 rev *180 deg/ pi rad * .32 s = 63.36 degrees
Explanation:
63.36 estimated to 63 so 63
The angle in degrees where 33 rpm record turn in 0.32 s should be considered as the 63 degrees.
Calculation of the angle:Since we know that1 rev = 2(pi) rad
So here pi(rad) = 180 degrees
Now for 33 rpm it should be like
= 33 rev/min * 1 min/60s * (2*pi)rad/1 rev *180 deg/ pi rad * .32 s
= 63.36 degrees
= 63 degrees
hence, The angle in degrees where 33 rpm record turn in 0.32 s should be considered as the 63 degrees.
Learn more about an angle here: https://brainly.com/question/3394547
A tennis ball moves 16 meters northward, then 22 meters southward, then 12 meters northward, and finally 32 meters southward.
Define conductor and insulator, including how the resistance is different in the two, and give at least one example of each.
Answer:
Those substances which can conduct electricity are called conductors, while those substances which don't conduct electricity are called insulators.
Resistance is the obstruction provided by the material through which the current passes,so since conductors conduct electricity and insulators don't,so the obstruction i.e resistance provided by the conductor must be less,while insulators being unable to conduct electricity,has very high resistance.
Example of conductor is copper
Example of insulator is plastic
Which is NOT a form of erosion?
a
Rivers moving dirt
b
Water running downhill, carving out the land and pushing dirt to the side
c
Water evaporating and condensing
d
Heavy winds blowing soil to other locations
HELP ASAP
Answer:
water evaporating and condensing, because that's the water cycle and it isnt eroding anything
A popular ride at an amusment park lifts
customers up to a height of 50 m and then
drops them threw a displacement of 50 m
before slowing them to a stop. How fast
are the customers going at the 50 m
mark?
Answer:
[tex]31.32\ m/s[/tex]
Explanation:
[tex]We\ are\ given\ that:\\Height\ to\ which\ there're\ lifted=50m\\Displacement\ during\ the\ descent=50m\\Now,\\In\ order\ to\ find\ the\ velocity\ of\ the\ customers\ at\ 50\ m,\\We\ can\ use\ the\ Third\ Equation\ Of\ Motion,\ which is:\\2as=v^2-u^2\\As\ we\ know\ that,\\Acceleration\ due\ to\ gravity=9.81\ m/s^2\ or\ roughly\ 10\ m/s^2\\Displacement=50\ m\\Initial\ velocity=0\ m/s^2\\ [As\ they\ stop\ when\ they\ reach\ the\ maximum\ height\ of\ 50\ m\\ and\ begin\ their\ descent][/tex]
[tex]By\ reconstructing\ the\ Third\ Equation\ Of\ Motion,\ we\ have:\\2gs=v^2\\Hence,\\v^2=2*9.81*50 \\v^2=981\ m^2/s^2 \\v=\sqrt{981\ m^2/s^2} \\v=31.32\ m/s[/tex]
A tsunami, an ocean wave generated by an earthquake, propagates along the open ocean at 700 km/hr and has a wavelength of 750 km. What is the frequency of the waves in such a tsunami?A. 6.8 HzB. 0.93 HzC. 0.00026 HzD. 1.1 HzE. 0.15 Hz
Answer:
C) 0.00026 Hz
Explanation:
In any wave, there exists a fixed relationship between the speed v, the frequency f and the wavelength λ, as follows:[tex]v = \lambda * f (1)[/tex]
Replacing by the givens in (1), and solving for f, we get:[tex]f = \frac{v}{\lambda} = \frac{700km/hr}{750 km} = 0.93 1/hr (2)[/tex]
Converting the units to Hz (1/sec), we get:[tex]f = 0.93 \frac{1}{hr} *\frac{1 hr}{3600sec} = 2.6e-4 = 0.00026 Hz (2)[/tex]
The answer C. is the right one.A gas cylinder holds 0.10 mol of O2 at 150 C and a pressure of 3.0 atm. The gas expands adiabatically until the pressure is halved
Part A
What is the final volume?
Part B
What is the final temperature?
Answer:
V2 = 1.899*10^-3 m^3
T2 = 347.125 K
Explanation:
Using gas law, we know that
PV = nRT,
Where
V1 = 0.00115743 m^3.
gamma = 1.4
Now, when we solve for final volume, V2 we get
V2 = V1/((P2/P1)^(1/gamma))
V2 = 1.899*10^-3 m^3
Using the same law and method, when we try to solve for the temperature, we find that the final temperature, T2 is
T2 = T1*((V1/V2)^(gamma-1))
T2 = 347.125 K
The final volume is 1.899*10^-3 m^3
And, the final temperature is 347.125 K
Gas law:here we used gas law,
we know that
PV = nRT,
Here
V1 = 0.00115743 m^3.
gamma = 1.4
Now final volume is
V2 = V1/((P2/P1)^(1/gamma))
V2 = 1.899*10^-3 m^3
Now the final temperature is
T2 = T1*((V1/V2)^(gamma-1))
T2 = 347.125 K
Learn more about volume here: https://brainly.com/question/13011592
You are interested in a new sports car that can go from 0 m/s to 120 m/s in 12 s. What is the acceleration of the car?
Formula
image
A.
0.1
m
s
2
B.
10
m
s
2
C.
60
m
s
2
D.
1440
m
s
2
Answer:
A
Explanation:
Option B) 10m/s² is the correct answer.
Hence, the acceleration of the new sports car in the given period of time is 10m/s².
What is Motion?Motion is simply the change in position of an object over time.
From the First Equation of Motion;
v = u + at
Where v is final velocity, u is initial velocity, a is acceleration and t is time elapsed.
Given the data in the question;
Initial velocity of the sport car u = 0m/sFinal velocity of the sport car v = 120m/sElapsed time t = 12sAcceleration of the sports car a = ?To determine the acceleration of the new sports car, we substitute our given values into the expression above.
v = u + at
120m/s = 0m/s + (a × 12s)
a × 12s = 120m/s - 0m/s
a × 12s = 120m/s
a = 120m/s ÷ 12s
a = 10m/s²
Option B) 10m/s² is the correct answer.
Hence, the acceleration of the new sports car in the given period of time is 10m/s².
Learn more about Equations of Motion here: brainly.com/question/18486505
One of two 25-year-old identical twins begins a trip on a spaceship traveling at 0.8 c while her twin remains on Earth. The twin on Earth tracks her twin's trip for 10 years. After ten years, what age is the twin on the spaceship according to the twin on Earth?
a. 41.7 years old.
b. 35 years old.
c. 31 years old.
d. 37.5 years old.
I
2800000 kg
Fig. 2.1
The total mass of the rocket and its full load of fuel is 2.8 106 kg. The constant force provided by
the rocket's motors is 3.2 x 107N.
32000000 N.
(a) Calculate
(i) the total weight of the rocket and the fuel.
weight =
Answer:
W = 27468000 [N] or 27.47 [kN]
Explanation:
The weight of a body is defined as the product of mass by gravitational acceleration.
[tex]W = m*g[/tex]
where:
W = weight of the rocket with fuel [kg]
m = mass = 2800000 [kg]
g = gravity acceleration = 9.81 [m/s²]
Now we can solve:
[tex]W = 2800000*9.81\\W = 27468000 [N][/tex]
A horizontal force of 350 NN is exerted on a 2.0-kgkg ball as it rotates (at arm's length) uniformly in a horizontal circle of radius 0.90 mm. Part A Calculate the speed of the ball. Express your answer to two significant figures and include the appropriate units.
Answer:
The value is [tex]v = 12.6 \ m/s[/tex]
Explanation:
From the question we are told that
The horizontal force is [tex]F_h = 350\ N[/tex]
The mass of the ball is [tex]m = 2.0 \ kg[/tex]
The radius is [tex]r = 0.90 \ m[/tex]
Generally the speed of the ball is mathematically evaluated from the formula for centripetal force as
[tex]F_ h = \frac{mv^2}{ r }[/tex]
=> [tex]v = \sqrt{\frac{ F_h * r }{ m }}[/tex]
=> [tex]v = \sqrt{\frac{ 350 * 0.9 }{ 2 }}[/tex]
=> [tex]v = 12.6 \ m/s[/tex]
two spheres A and B are projected off the edge of a 1.0 m high table with the same horizontal velocity . sphere A has a mass of 20.g and sphere B has a mass of 10.g.
If both spheres leave the edge of the table at the same instant, sphere A will land
a. at some time after sphere B.
b. at the same time as sphere B.
c. at some time before sphere B.
d. There is not enough information to decide.
A would land before since its heavier
The surface tension of the alcohol propanol in air has a value of 23.70 units
and the surface tension of water in air is 72.80 units. Which two statements
are true?
A. Propanol will have a flatter meniscus than water because the
forces between the molecules are smaller.
B. Propanol will have a higher boiling point than water because the
forces between the molecules are greater.
C. Propanol will have a more curved meniscus than water because
the forces between the molecules are greater.
D. Propanol will have a lower boiling point than water because the
forces between the molecules are smaller.
Answer:
A & D your welcome
Propanol surface is more flattered and has less boiling point than that of water.
To determine the correct statements among all the statements, we need to know about the surface tension.
What is surface tension?Surface tension is defined as force per unit length.More the surface tension, more the force between the molecules to keep the molecules together.What does happen, if molecules have more force of attraction?If the molecules have large force of attraction, more heat will be required to break the bonds between them. So the boiling point increases. Also with more force of attraction, the surface of the liquid becomes less flattered.Since, propanol has less surface tension than that of water, so its surface is more flattered and has less boiling point than that of water.
Learn more about the surface tension here:
brainly.com/question/277477
#SPJ2
A cross-country skier moves 36 meters eastward, then 44 meters westward, and finally 22 meters eastward.
Complete question is;
A cross-country skier moves 36 meters eastward, then 44 meters westward, and finally 22 meters eastward. What's the Magnitude and Direction?
Answer:
Magnitude = 14 m
Direction = eastward
Explanation:
The magnitude and direction of this cross-country skier will be the gotten from his displacement.
Now, from directions of 4 cardinal points, we can say that the eastward direction is on the positive x-axis and is positive while the westward direction is on the negative x-axis and is negative.
From those positive and negative signs above, we can represent the movement of the skier as;
moves 36 meters eastward = 36 m
moves 44meters westward = -44 m
Moves finally 22 meters eastward = 22
Thus, displacement will be:
36 - 44 + 22 = 14
It is positive, and thus, the magnitude is 14 and the direction is east ward.
Find the current if 55 C of charge pass a particular point in a circuit in 5 seconds.
Answer:
The current is 11 Amperes
Explanation:
Electric Current
The electric current is defined as a stream of charged particles that move through a conductive path.
The current intensity can be calculated as:
[tex]\displaystyle I=\frac{Q}{t}[/tex]
Where:
Q = Electric charge
t = Time taken by the charge to move through the conductor
The current intensity is often measured in Amperes.
The charge passing through a point in a circuit is Q= 55 c during t=5 seconds, thus the current intensity is:
[tex]\displaystyle I=\frac{55}{5}[/tex]
I = 11 Amp
The current is 11 Amperes
1+1=?
FIRST ONE TO ANSWER GETS BRAINLIEST!
Answer:
Thx for points merry Christmas answer 2
Explanation:
Answer:2
Explanation:
A wagon with a mass of 30kg is accelerated across a level surface at 2.4 m/s^2. What net forces acts on the wagon?
Answer:
72 NExplanation:
The force acting on an object given it's mass and acceleration can be found by using the formula
force = mass × acceleration
From the question we have
force = 30 × 2.4
We have the final answer as
72 NHope this helps you
A 10.0kg object is moving at 1 m/s when a force is applied in the direction of the objects motion, causing it to speed up to 4 m/s. If the force was applied for 5s what is the magnitude of the force
Answer:
F = 6[N].
Explanation:
To solve this problem we must use the principle of conservation of linear momentum, which tells us that momentum is conserved before and after applying a force to a body. We must remember that the impulse can be calculated by means of the following equation.
[tex]P=m*v\\or\\P=F*t[/tex]
where:
P = impulse or lineal momentum [kg*m/s]
m = mass = 10 [kg]
v = velocity [m/s]
F = force [N]
t = time = 5 [s]
Now we must be clear that the final linear momentum must be equal to the original linear momentum plus the applied momentum. In this way we can deduce the following equation.
[tex](m_{1}*v_{1})+F*t=(m_{1}*v_{2})[/tex]
where:
m₁ = mass of the object = 10 [kg]
v₁ = velocity of the object before the impulse = 1 [m/s]
v₂ = velocity of the object after the impulse = 4 [m/s]
[tex](10*1)+F*5=10*4\\10+5*F=40\\5*F=40-10\\5*F=30\\F=6[N][/tex]
A disk rotates at a constant angular velocity of 30 degrees per second. Consider a point on the edge of the disk. Through how many degrees has it rotated after 3 seconds?
Answer:
The disk covers a rotation of 90º after 3 seconds.
Explanation:
Since the disk rotates at constant angular speed, we can determine the change in angular position ([tex]\Delta \theta[/tex]), measured in sexagesimal degrees, by the following kinematic formula:
[tex]\Delta \theta = \omega\cdot \Delta t[/tex] (1)
Where:
[tex]\omega[/tex] - Angular velocity, measured in sexagesimal degrees per second.
[tex]\Delta t[/tex] - Time, measured in seconds.
If we know that [tex]\omega= 30\,\frac{\circ}{s}[/tex] and [tex]\Delta t = 3\,s[/tex], then the change in angular position is:
[tex]\Delta \theta = \left(30\,\frac{\circ}{s} \right)\cdot (3\,s)[/tex]
[tex]\Delta \theta = 90^{\circ}[/tex]
The disk covers a rotation of 90º after 3 seconds.
When an element ejects an alpha particle, the mass number of that element
A.reduce by 4.
B.remains unchanged.
C.increase by 1.
D. reduce by 1.
Answer:
A.reduce by 4.
Explanation:
In Chemistry, an alpha particle which is typically a helium nucleus has an atomic mass (number of nucleons) of four (4). Therefore, the ejection of an alpha particle by any chemical element simply means that, the mass number of that particular chemical element would be reduced by four (4).
Basically, this process is referred to as an alpha decay and can be defined as a radioactive disintegration of a chemical element that causes it to emit an alpha particle and as a result reducing its mass number by four (4).
Hence, when an element ejects an alpha particle, the mass number of that element reduces by 4.
Which structures are found in the middle ear? Check all that apply.
A. hammer
B. anvil
C. ear canal
D. cochlea
E. ear drum
F. stirrup
Answer:
E, A, B, F
Explanation:
The Middle Ear contains:
eardrum.
cavity (also called the tympanic cavity)
ossicles (3 tiny bones that are attached) malleus (or hammer) - long handle attached to the eardrum. incus (or anvil) - the bridge bone between the malleus and the stapes. stapes (or stirrup) - the footplate; the smallest bone in the body.
Answer: rawr
Explanation:
hammer
anvil
ear drum
stirrup
What is the condition required of the phase difference (in radians) between two waves with the same wavelength if these waves interfere constructively?
a. (2m +1)π where m= 0, +1, +2, etc.
b. mπ where m = 0, +1, +2, etc.
c. 2mπ where m = 0, +1, +2, etc.
d. (m+1)π where m = 0, +1, +2, etc.
Answer:
c.
Explanation:
In order to two waves with the same wavelength can interfere constructively, their crests and valleys must coincide in space, so the phase difference must be equal to an integer number of wavelengths, i.e. m *(2 π rad), where m= 0, +1, +2, etc.This is equal to the stated by the answer c) , so c) it's the right answer.An astronaut stands on the surface of an asteroid. The astronaut then jumps such that the astronaut is no longer in contact with the surface. The astronaut falls back down to the surface after a short time interval. Which of the following forces CANNOT be neglected when analyzing the motion of the astronaut?
Asteroids are known through the help of artificial gravity, to have small gravity. The forces that cannot be neglected when analyzing the motion of the astronaut is that the gravitational force between the astronaut and the asteroid.
The gravitational force between two objects is said to be inversely proportional to the distance between them when squared. Therefore, when an individual halve the distance then the force increases by four times.
Unbalanced forces are simply known to be brought about due to a change in motion, speed, and/or direction. If two forces act in the same direction on an object, the net force is said to be equal to the sum of the two forces.
Learn more from
https://brainly.com/question/2784184