A ball having a mass of 0.20 kilograms is placed at a height of 3.25 meters. If it is dropped from this height, what will be the kinetic energy of the ball when it reaches 1.5 meters above the ground?

Question

anonymous · Answer

@chmvijay

unklerhaukus · Answer

So can you first find the potential energy at this height ?

unklerhaukus · Answer

As the object falls the potential energy is converted to kinetic energy

anonymous · Answer

since no external force is being applied on the object, the energy of the object is conserved. use the law of conservation of energy to calculate the kinetic energy.

anonymous · Answer

im still a little lost? :l

unklerhaukus · Answer

what do you get for the potential energy at before the ball falls ?

anonymous · Answer

Okay @UnkleRhaukus in order to find PE i need the acceleration due to gravity right?

unklerhaukus · Answer

yeah it should be about 9.8 m/s^2

unklerhaukus · Answer

(assuming your on earth)

anonymous · Answer

How did you get that?

unklerhaukus · Answer

On the surface of earth acceleration due to gravity is about  9.8 m/s^2

anonymous · Answer

oh okay so now i just calculate?

anonymous · Answer

Wait, i look for PE first or the KE?o.o

unklerhaukus · Answer

First, find the Potential energy before the object is dropped.

then, find the potential energy at 1.5 meters above the ground

The difference is the energy that has gone to kinetic energy

anonymous · Answer

Okay before the ball is dropped it will be 6.37meters/second if im not mistaking

unklerhaukus · Answer

yes,

anonymous · Answer

And then do i add 1.5 or subtract it from the given hieght?

unklerhaukus · Answer

but the units for energy is      kg m^2 /s^2   or     J

unklerhaukus · Answer

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unklerhaukus · Answer

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