Question

1. A rocket starts at rest and accelerates up at 61.2 m/s² for 1.41 s. What maximum height does it reach?

2. An Atwood machine is made with masses 8.9 kg and 4.9 kg. What is its acceleration?

3.A block slides down a 47.4º at 2.55 m/s^2. What is the coefficient of friction?

Answer 1

1) If u be the initial velocity and after accelerating at rate f for time t then we have the dynamics equation

here the roclet starts from rest so, u=0 m/s

So we have

This is the maximum height reached by the rocket

2) For an Atwood machine of mass m1 and m2, and the mass m2 is moving downward with acceleration a we have

g is the acceleration due to gravity

Putting the values,

3) For an incline, coefficient of friction is given by