# With what speed does the mass hit the ground at the bottom of the cliff? The following takes place at a colony on the Moon some time in the distant future:A 40 kg cannon is loaded with a 10 kg...

With what speed does the mass hit the ground at the bottom of the cliff?

The following takes place at a colony on the Moon some time in the distant future:

A 40 kg cannon is loaded with a 10 kg cannonball and mounted on a 6 kg platform with wheels very low to the ground. The wheeled platform is pushed and moves forward at 3 m/s horizontally. When the cannonball is fired out, the cannon recoils (backward) with a velocity of 2 m/s relative to the ground. The cannonball then strikes a large solid block that weighs 32N and is sitting on the edge off a 50 m high cliff and becomes embedded in it. The combined mass is shot horizontally off the cliff.

nessus | Certified Educator

calendarEducator since 2011

starTop subjects are Science and Arts

Let m1 = mass cannon+platform =46kg.

m2 = mass  ball = 10kg

u1 = u2 = initial horizontal velocity of m1+m2 = 3ms^-1

v1 = final velocity of cannon and platform = -2ms^-1

Use m1u1 + m2u2 = m1v1 + m2v2 to find m2v2 the horizontal momentum of the ball after firing. Rearranging:

m2v2 = m1u1 +  m2u2 - m1v1

= (46 x 3) + (10 x 3) - (46 x...

(The entire section contains 175 words.)