Answer:
Acceleration, 
Explanation:
Given that,
The plane is at rest initially, u = 0
Final speed of the plane, v = 72.2 m/s
Time, t = 29 s
We need to find the average acceleration for the plane. It can be calculated as :



So, the average acceleration for the plane is
. Hence, this is the required solution.
The elephant and the mouse having zero weight in a gravity free space will not bump into you at the same effect.
<u>Explanation:
</u>
When both are in a gravity free space, the weights are zero, as we know that the


But when they will acquire the speed of same magnitude, say v, their different masses will acquire different momentum, which will make the difference in effect while bumping.

And as we know
Therefore, effect of impact by elephant will be more than that of mouse
. An elephant breaking into you will take you back faster than a mouse in space hits you.
During convection of air currents, cool air sinks. <em>(b)</em>