Why does freely falling body have constant acceleration but body on inclined plane have constant velocity?

Question

if length of inclined plane=35cm,angle of elevation=48degree,height of the top point from ground=28cm, what is the ACCELERATION,final velocity,time taken to cover the length,force acting on the body of mass=100gms.

Answer 1

I do not agree to your question,i.e. a constant velocity on an inclined plane.When there is an inclination,velocity can not be constant.Accelaration will be there.

Answer 2

Bodies on inclined also accelerate. Hence, no constant velocity.

Answer 3

Sir Isaac Newton conducted his experiments using inclined planes, he showed clearly that the objects moving down those planes had constant acceleration.

Answer 4

dear as far as my physics strong it says that there is no such thing like constant acceleration.acceleration is itself a change in the velocity.

Answer 5

When you are freefalling you will pick up speed the further you go. on a plane the fall speed is controled by the pilot.

Answer 6

Actually the body on the inclined plane also has a constant acceleration. The force of gravity can be broken into two components: one perpendicular to the plane and the other along the plane.

L = length of inclined plane = 28 cm = 0.28 meters

T = angle of elevation = 48 degrees

m = mass of block = 100 gm = 0.1 kg

g = acceleration of gravity = 9.8 m/s^2

Force perpendicular = mg cos(T)

Force along = mg sin(T)

This is not so difficult to see. Imagine the plane is flat on the earth then T = 0 and the perpendicular force is just gravity and the force along the plane is 0 as it should be.

The force perpendicular to the plane does not matter since the plane is pushing with an equal force in the opposite direction.

So the force acting on the block is just:

F = mg sin(T) = 0.1(9.8)sin(48)

F = 0.728 N

Since force is mass times acceleration, the acceleration of the block is just:

a = g sin(T) = 9.8sin(48) = 7.2828 m/s^2

The time it takes to move down the plane can be found from:

distance moved = s = (1/2)at^2

t = SQRT(2s/a) = SQRT(2*0.28/7.2828)

t = 0.2675 seconds

Final velocity is just v = at (since the block starts at rest)

v = (7.2828)(0.2675) = 1.95 m/s