Using standard formulae, derive an expression for the final speed of a falling object in terms of its change in height. Assume zero air resistance or other resistive forces.

Ek = (1/2)mv2

Ep = mg(dh)

Set these equal to each other, because of conservation of energy:

(1/2)mv2 = mg(dh)

Cancel the mass:

(1/2)v2 = g(dh)

v2 = 2g(dh)

v = (2g(dh))1/2

DL

Related Physics GCSE answers

All answers ▸

A sequence is defined by the recurrence relation u(n+1) = 1/3 u(n) + 10 with u(3) = 6 . Find the value of u(4) and the limit of the sequence.


Describe the different forces upon a falling object with reference to Newton's first law.


A skydiver is at a height of 10,000 m. Assuming no air resistance, how fast is the skydiver travelling at 9,990 m above the ground?


Explain, in terms of pressure, how straws draw water into your mouth.