Question

a cannonball is fired with a speed of 76 m/s from the top of a cliff. It strikes the plane below with a speed of 89 m/s. if we neglect air friction, how high is the cliff

Answer 1

we use the formula,

`v {}^(2) = u {}^(2) + 2gh`

`89 {}^(2) = 76 {}^(2) + 2(10)h`

`h = (89 {}^(2) - 76 {}^(2) ) / 20`

h= 107 m