The gravitational acceleration at any distance r is given by

where G is the gravitational constant, M the Earth's mass and r is the distance measured from the center of the Earth.
The Earth's radius is
, so the meteoroid is located at a distance of:

And by substituting this value into the previous formula, we can find the value of g at that altitude:

Answer:
Option A
Explanation:
At segment T-U, the substance changes from a liquid to a gas and does not change temperature.
The reason is because latent heat of vaporisation allows for the absorption of heat in the change of state and temperature remains constant until it has fully changed state.
Answer:
B) the change in momentum.
Explanation:
The impulse is defined as the product between the force applied on an object (F) and the duration of the collision (
):
(1)
We can rewrite the force by using Newton's second law, as the product between mass (m) and acceleration (a):

So, (1) becomes

Now we can also rewrite the acceleration as ratio between the change in velocity and change in time:
. If we substitute into the previous equation, we find

And the quantity
is equivalent to the change in momentum,
.
Energy flows with kinetic energy
Answer:

Explanation:
Given that,
The wavelength of light, 
We need to find the frequency of the light. We know that,

So, the required frequency of light is equal to
.