The rate at which work is done is called ___

A turtle moves at an average speed of 0.2m/S towards the finish line that is 80m away from the starting line. A rabbit,racing wi

klasskru [66]

Answer:

5.6mls

Explanation:

3 0

2 years ago

The length of a certain wire is kept same while its radius is doubled. what is the new resistivity of this wire?

anastassius [24]

The text does not specify whether the resistance R of the wire must be kept the same or not: here I assume R must be kept the same.

The relationship between the resistance and the resistivity of a wire is
$\rho = \frac{AR}{L}$
where
$\rho$ is the resistivity
A is the cross-sectional area
R is the resistance
L is the wire length

the cross-sectional area is given by
$A=\pi r^2$
where r is the radius of the wire. Substituting in the previous equation ,we find
$\rho = \frac{\pi r^2 R}{L}$

For the new wire, the length L is kept the same (L'=L) while the radius is doubled (r'=2r), so the new resistivity is
$\rho' = \frac{\pi r'^2 R}{L'}= \frac{\pi (2r)^2 R}{L}=4 \frac{\pi r^2 R}{L} = 4 \rho$
Therefore, the new resistivity must be 4 times the original one.

5 0

3 years ago

Read 2 more answers

When an object radiates heat, the strength of this radiation far from the object decreases when distance from the source increas

Andrew [12]

Answer:

The source of cosmic background radiation filled the entire universe.

Explanation:

D:The source of cosmic background radiation filled the entire universe.

7 0

2 years ago

Read 2 more answers

1.what is gravity?(in your own words)

olga_2 [115]

Answer:

1.Gravity is an invisible force that pulls objects toward each other

2.The suns gravity pulls the planet towards the sun which changes the straight line of direction into a curve

That keeps the planet moving in an orbit around the sun

hope it helped:)

8 0

2 years ago

You are riding in the passenger seat of a car as it goes around a tight turn. You slide across the seat to the passenger side do

DochEvi [55]

Answer:

1. b. The door is exerting a centripetal force on you that balances the centrifugal force of the turn.

2. b. There is no net force acting on the object.

Explanation:

1. This is because as you move to the right due to the centrifugal force of the turn, a corresponding centripetal force acts on you due to the door which does not allow you fall out of the car since,<u> the door is exerting a centripetal force on you that balances the centrifugal force of the turn. </u>

So, the answer is b

2. This is because, since the object moves at a constant speed and thus does not accelerate, no net force can act on it since, a net force would imply that the object accelerates. Note that a constant speed does not imply that no force acts on it. It only shows that the resultant or net force is zero since the object does not accelerate.

So, <u>there is no net force acting on the object. </u>

So, b is the answer.

6 0

2 years ago

The rate at which work is done is called ____.