Question

A pinball has a mass of 0.002 kg and a speed of 10m/s. If it rolls up a 30degree ramp, what will its height be when it comes to a stop?

Answer 1

Given: m= 0.002 kg , v = 10 m/s , = 30°

Solution:

Step:1 Energy at bottom of ramp

Energy of pinball at bottom of ramp is given by:

E= (1/2)mv² = (1/2)(0.002 kg)(10 m/s)²

E = 0.1 J

Step:2 Energy at the top of ramp where ball comes to a stop

When pin ball comes to a stop , then total energy of ball at top of ramp would be only its potential energy.

i.e. PE = mgh

Where h is the height of the ramp.

i.e. PE = (0.002 kg)(9.81 m/s²)(h)

=( 0.01962)h

Step:3 Applying energy of conservation to get height

By conservation of energy , E = PE

i.e. 0.1 J = (0.01962)h

h = 0.1/0.01962= 5.1 m

Hence the height of ramp when pinball comes to a stop is 5.1 m