An apple drops from the tree and falls freely. The apple is originally at rest a height H0 above the ground. The ground is covered with a thick lawn, which is made of blades of grass of height h. When the apple enters the grass, it slows down at a constant rate so that its speed is 0 when it reaches ground level.

A)Find the speed of the apple just before it enters the grass

B) Find the acceleration of the apple while it is in the grass

Explanation:

The distance travelled in the free fall is H - h  

Since the apple originally started from rest we can use v^2 =  u^2 + 2 x g x s  where v is the final velocity, g the accln due to gravity and s the distance travelled and u is the initial velocity = 0

So the velocity just before it enters the grass is sq rt [2 x g x (H - h)]

Once in the grass, it slows down at a constant rate which means that the acceleration (a) during this period is constant.

So once again using the same formula we have v = O and u = sq rt[2 x g x (H-h)]

so since v^2 = u^2 + 2 x a x s then  

O^2 = 2 x g x (H-h) + 2 x a x h

{O^2 - 2 x g x (H - h)}/(2 x h) = a

a

explanation:

no diagram was provided, but i'm guessing it's the one i've attached to my answer.

here, a mechanical force turns the rod.   this generates an electric current in the coil, which powers the bulb.

weight of the box is given as

here this is placed on the inclined of angle 42 degree

now this weight will have two components one is along the incline other is perpendicular to it

so here we need to apply a force parallel to incline opposite to its component of weight

so here the component of weight is given as

here we have

so it requires 75 n force to move it upwards