Someone help me please it’s urgent
A child sits on a merry-go-round, 1.5 meters from the center. The merry-go-round is turning at a constant rate, and the child is observed to have a radial acceleration of 2.3 m/s2. How long does it take for the merry-go-round to make one revolution
Answer:
5 .07 s .
Explanation:
The child will move on a circle of radius r
r = 1.5 m
Let the velocity of rotation = v
radial acceleration = v² / r
v² / r = 2.3
v² = 2.3 r = 2.3 x 1.5
= 3.45
v = 1.857 m /s
Time of revolution = 2π r / v
= 2 x 3.14 x 1.5 / 1.857
= 5 .07 s .
The merry-go round will take 5.07 s to complete one complete revolution.
Given data:
The distance of child from the center is, r = 1.5 m.
The magnitude of radial acceleration is, [tex]a = 2.3 \;\rm m/s^{2}[/tex].
Since, the child is on merry-go round, which is undergoing a rotational motion. And radial acceleration means that it is under the acceleration, whose value is given as,
[tex]a=\dfrac{v^{2}}{r}\\\\v=\sqrt{a \times r}[/tex]
Here, v is the linear velocity.
Solving as,
[tex]v=\sqrt{2.3 \times 1.5} \\\\v=1.857 \;\rm m/s[/tex]
Now, we to obtain the time taken by merry-go round to complete one revolution. Then the expression for the time taken to complete one revolution is,
[tex]T=\dfrac{2 \pi r}{v}\\\\T=\dfrac{2 \pi \times 1.5}{1.857}\\\\T = 5.07 \;\rm s[/tex]
Thus, we can conclude that the merry-go round will take 5.07 s to complete one revolution.
Learn more about the centripetal acceleration here:
https://brainly.com/question/14465119
When water changes from a gas in the atmosphere to a liquid droplet in a cloud, this is known as
Group of answer choices
transpiration
condensation
evaporation
precipitation
Answer:
Condensation
Explanation:
Answer:When water changes from a gas in the atmosphere to a liquid droplet in a cloud, this is known as
Group of answer choices
transpiration
condensation
evaporation
precipitation,←, that one is right
Explanation: so ur answer is precipitation
things that affects the demand for electricity
1. A person weighs 155 lbs and is walking 3.1 miles per hour. How much kinetic energy does the person have? (Keep in mind, 1 kg is 2.2 lb, and 1 m/s is 2.24 mi/h.)2. What is the kinetic energy of a 5 g bullet travelling 400 m/s?
3. Is it possible to have a negative KE? Why or why not?
Answer:
Explanation:
Kinetic energy is expressed as;
KE =1/2 mv²
M is the mass
v is the velocity of the object
1) Given
Mass = 155lb
Velocity = 3.1mi/hr
Since 1kg = 2.2lb
x = 155lb
x= 155/2.2
x = 70.45kg
Also
1m/s = 2.24mi/hr
y = 3.1mi/hr
y = 3.1/2.24
y = 1.384m/s
KE = 1/2(70.45)(1.384)²
KE = 0.9577×70.45
KE = 67.47Joules
2) M = 5g =0.005kg
V = 400m/s
KE = 1/2(0.005)400²
KE = 80000×0.005
KE = 400Joules
3} Since a body decelerates (negative acceleration) this mean that the velocity of a body can be a negative value showing that it is possible for a moving body to possess negative kinetic energy.
How long will it take a 2190 W motor to lift a 1.47 x 104 g box, 6.34 x 104 mm vertically.
Answer:
4.2s
Explanation:
Given parameters:
Power = 2190W
Mass of box = 1.47 x 10⁴g
distance = 6.34 x 10⁴mm
Unknown:
Time = ?
Solution:
Power is the rate at which work is done;
Mathematically;
Power = [tex]\frac{work done}{time}[/tex]
Time = [tex]\frac{work done}{power}[/tex]
Work done = weight x height
convert mass to kg;
100g = 1kg;
1.47 x 10⁴g = 14.7kg
convert the height to m;
1000mm = 1m
6.34 x 10⁴mm gives 63.4m
Work done = 14.7 x 9.8 x 63.4 = 9133.4J
Time taken = [tex]\frac{9133.4}{2190}[/tex] = 4.2s
A pendulum is transported from sea-level, where the acceleration due to gravity g is 9.80 m/s2, to the bottom of Death Valley. At this location, the period of the pendulum is decreased by 3.00%. What is the value of g in Death Valley
Answer: the value of g in Death Valley is 10.417 m/s²
Explanation:
Given that;
acceleration due to gravity at the point is g = 9.8 m/s²
Lets say the acceleration due to gravity at the bottom of Death valley is g'
as the period of the pendulum is decreased by 3.00%
T' = 0.97 T
T is the period of the pendulum at sea level and T' is the period of the pendulum at bottom of Death valley
therefore from the relation
T = 2π√(l/g)
g'/g = T²/T'²
g' = (T²/ (0.97T)²)g
g' = 1.063g
g' = 10.417 m/s²
therefore the value of g in Death Valley is 10.417 m/s²
if an object is moving with a velocity of 25m/s, an acceleration of 5m/s and has a travel time of 5s, what is the final velocity of the object?
V = at + V0
where v0 is the initial speed, a is the acceleration and t is the time.
So:
v = 5m/s^2*5s + 25m/s = 50 m/s
If the brakes are applied and the speed of the car is reduced to 13 m/s in 14 s, determine the constant deceleration of the car.Express your answer to three significant figures and include the appropriate units. Assume ais negative if it acts in the opposite sense to the positive velocity.
Answer:
Explanation:
v = u + at
v is final velocity , u is initial velocity , a is acceleration and t is time .
here v = 0 , u = 13 m /s , t = 14 s
putting the values
0 = 13 + 14 a
a = 13 / 14 m /s²
= - .9286
= - 0.929 m /s²
A current of 15 Amps flows through a circuit with a resistance of 0.10 Ohms. What is the voltage?
A. 0.006 Volts
OB. 1.5 Volts
O C. 15 Volts
D. 150 Volts
Voltage = (current) x (resistance) (Ohm's law)
Voltage = (15 A) x (0.10 ohm)
Voltage = 1.5 volts (B)
A student builds an electromagnet using a battery, an iron nail, and some insulated wire. The wire is wrapped around the nail 50 times, then connected to the
battery. What changes could the student make to increase the strength of the electromagnet?
1. wrap more wire around the nail
2. increase the voltage of the battery
3. use a switch to turn the electromagnetic on and off
4. increase the size of the nail
A. 1 and 2
B. 2 and 4
C. 1,2 and 4
D. 1,2,and 3
Answer:
a
Explanation:
its right
To increase the electromagnet's strength, the student must enlarge the nail, wrap more wire around the nail, and increase the voltage of the battery. Option c is the correct answer.
How does an electromagnet work?The mechanics of an electromagnet are not overly complicated. It is accomplished by wrapping a length of conductive wire, usually copper, around a metal object.Until electricity is introduced, this appears to be nothing more than a jumbled collection of parts, similar to Frankenstein's monster. An electromagnet, on the other hand, does not require a storm to be activated. A current is introduced and flows through the wire, which can come from a battery or another source of power.As a result of the magnetic field created around the coiled wire, the metal is magnetized as if it were a permanent magnet. Electromagnets are useful because they can be activated and deactivated by closing and opening a circuit.To learn more about electromagnet, refer to
brainly.com/question/7382276
#SPJ2
A water molecule is made up of one oxygen and two hydrogen atoms. Why is water considered a pure substance?
Answer:
A mixture is when two or more substances combine physically together.
However, in water, two hydrogen atoms combine with one oxygen atom chemically, forming a new substance that has properties different from hydrogen alone or oxygen alone.
Explanation:
Does electric and magnetic objects both have north and south poles
Explanation:
hope this answer was helpful
What type of numbers in a measurement are always significant?
Answer:
Non-zero digits
Explanation:
umm (ꏿ﹏ꏿ;)
Answer:
There's three rules on determining how many important quantities are in a number: Non-zero digits are always predominant. Any zeros between two significant digits are always major. The final zero or dangling zeros in the decimal segment are really only important.
I hope this answered your question, have a nice day!
4). A basketball player shoots the ball in the air. It moves through the air
at 20 m/s and travels 25m. How long was the ball in the air? *
Let's start from this equation:
s = vt + s0
Know what it is? Of course you do. It's the equation used for knowing the position of an object in a certain period of time t.
s is space, v is speed, t is time, s0 is the initial space.
In this case the initial space is equal to 0 so our equation will become:
s = vt
Let's find t:
t = s/v
So:
t = 25m/20m/s = 1,25 s
---
Hope it was helpful. Have a great day!
QUESTION 13
Marci would describe almost a perfect person whenever her friends would ask her who she thought was
her ideal life partner. This "perfect" person would be ain)
O a prototype
b.reinforcer
oc. anagram
d. heuristic
1500 POINTS TO WHOEVER ANSWERS THIS FIRST!!!!!!!!!!
1. You drop a bowling ball 15m from the top of the science building. What is its
velocity as it impacts the ground?
2. A cheetah accelerates from 0 to 13m/s in 3 seconds. How far does it travel
during that time?
3. Your foolish friend shoots a bullet straight in the air at a muzzle velocity of
380 m/s. How high does the bullet go (neglecting air resistance)?
4. Your foolish friend shoots a bullet straight in the air at a muzzle velocity of
380 m/s. What is the bullets velocity when it falls back down and hits your
friend?
Answer: Multiply the time by the acceleration due to gravity to find the velocity when the object hits the ground. If it takes 9.9 seconds for the object to hit the ground, its velocity is (1.01 s)*(9.8 m/s^2), or 9.9 m/s.
Explanation:
When living things use chemical reactions to break down food, some of the energy is transformed into
OA. sound.
OB. heat.
OC. light
OD.waste
waste.
Answer:
OB. Heat
Explanation:
I hope this helped :)
Q17: The coefficient of linear expansion of steel is a = 11 x 10-6 / °C. A steel
ball has a volume of exactly 100 cm3 at 0°C. When heated to 100°C, its
volume becomes in (cm3):
A
B
D
E
100.33
100.11
100.0011
100.0033
None of them
Solution:
The coefficient of volume expansion
p = ΔV/V1Δt
3a = V2-V1/V1Δt
Given
a = = 11 x 10-6 / °C
V2 is the final volume
V1 is the initial volume = 100cm³
Δt = 100-0 = 100°C
Substitute
3(11 x 10-6) = V2-100/100(100)
33*10^-6 * 10000 = V2-100
33*10^-2 = V2-100
V2 = 100 + 0.33
V2 = 100.33
Hence the new volume is 100.33cm³
carter found the rock shown in the picture below near a river
Answer:
there's no picture
Explanation:
and what would the question be anyways?
Answer:
what is the question
Explanation:
Explain the procedures used and data recorded to identify a crystalline mineral based on its properties.
Answer:
By examining its external shape, color, hardness, etc.
Explanation:
A carbon ion with 10 electrons and 6 protons would have a charge of ?
Answer:
-4
Explanation:
Electrons are negative while protons are positive.
To find the charge, add the number of protons to the number of electrons.
6+(-10)
6-10
-4 is the charge
The Amazon rainforest has millions of trees down in South America. Pantanal, the largest wetland, or swamp, on Earth sits directly below the Amazon on a map. Explain this phenomenon using processes from the water cycle.
The subject is science just to let you know.
Answer:The Pantanal is, when the season changes of the river flow, the pantanal shrinks after a few river channels The amazon rainforest has a lot of trees.The vapor rises and condenses it into clouds.Water leaves the forest and comes back, the amazon leaves itself.If the amazon water was not to go by itself everything would be different.
Answer:
Nine, Brazil, Venezuela
Explanation:
pls answer this
quick as possible
Answer:
The answer is the 4th one
Explanation:
Good luck man
If a car traveled 50 meters in 2 seconds, what will the velocity be? (Write the answer with a number, on decimal if needed, then a space and the units, for example 5.7 m/s)
Answer:
The answer is 25 m/sExplanation:
The velocity of the car can be found by using the formula
[tex]v = \frac{d}{t} \\ [/tex]
d is the distance
t is the time taken
From the question we have
[tex]v = \frac{50}{2} \\ [/tex]
We have the final answer as
25 m/sHope this helps you
During the slowing down process, there is a time when the angular speed is 0.5 rev/s. The fan arm is 0.8 m long. What is the speed of a point on the end of the fan arm at this time
Answer:
2.51 m/s
Explanation:
Given that,
Angular speed of a fan, [tex]\omega=0.5\ rev/s = 3.14\ rad/s[/tex]
Length of the fan arm, r = 0.8 m
We need to find the speed of a point on the end of the fan arm at this time. Let v is the speed. It is given in terms of angular speed is given by :
[tex]v=r\omega\\\\v=0.8\times 3.14\\\\v=2.51\ m/s[/tex]
So, the required speed is 2.51 m/s.
Which statement correctly describes the diferences between positive and negative acceleration
O Positive acceleration describes a change in speed, negative acceleration desxibes no change in speed,
Positive acceleration describes no change in speed, negative acceleration desibes a change in speed,
Positive acceleration describes an increase in speed, negative sexeleration desnibes a decrease in speed
O Positive acceleration describes a decrease in speed, negative sideration describes an increase in sarees
Answer:The answer is this Positive acceleration describes an increase in speed, negative sexeleration desnibes a decrease in speed
Explanation:
Which of these is a base?
HNO3
vinegar
ammonia
HCl
The correct answer is Ammonia
What is the mechanical advantage of a nail puller where you exert a force 45 cm from the pivot and the nail is 1.8 cm on the other side? What minimum force must you exert to apply a force of 1250 N to the nail?
Answer:
Explanation:
Mechanical Advantage is the ratio of the distance of the input load (Li)from the pivot to the output load applied to the pivot(Lo)
MA = Li/Le
Given;
Li = 45cm
Lo = 1.8cm
MA = 45/1.8
MA = 25
Hence the mechanical advantage is 25
Also MA is expressed in terms of the force ratio which is the ratio of the Load to the effort applied.
MA = Load/Effort
Given
Load = 1250N
MA = 25
Effort = ?
Substitute
25 = 1250/Effort
Effort = 1250/25
Effort = 50N
Hence the minimum force exerted on the load is 50N
A 300 g object attached to a horizontal spring moves in simple harmonic motion with a period of 0.340 s. The total mechanical energy of the spring–object system is 3.00 J.
(a) What is the spring constant (in N/m)?
(b) What is the amplitude (in m) of the motion?
(c) What is the percentage change in amplitude of motion if the total energy of the system is increased to 5.00 J?
Answer:
Explanation:
angular velocity ω = 2π / T where T is time period of rotation .
= 2 x 3.14 / .34 = 18.47 rad /s
Total mechanical energy = 1/2 m ω²Α² where A is amplitude .
spring constant = k
[tex]\omega=\sqrt{\frac{k}{m} }[/tex]
m is mass
[tex]\omega^2=\frac{k}{m} }[/tex]
18.47² = k / .3
k = 102.34 N /m
b )
energy = 1/2 m ω²Α²
3 = .5 x 18.47² x A²
A² = .01759
A = .1326
13.26 cm .
c )
If energy becomes 5 J
5 = .5 x 18.47² x A²
A² = .0293
A = .1711
= 17.11 cm
percent increase
= (17.11 - 13.26 )x100 / 13.26
= 29%