A complex arrangement of pulleys forms what is called the block in a block and tackle. The rope used to lift the pulleys and the load is the tackle. A block and tackle is used to lift a truck engine, which has a weight and output force of nearly 8000 N. The input force required to lift this weight using the block and tackle is 400N. What is the mechanical advantage of the block and tackle?

Mechanical advantage = 20

Explanation:

Given:

Output force = 8,000 N

Input force = 400 N

Find:

Mechanical advantage

Computation:

Mechanical advantage = Output force / Input force

Mechanical advantage = 8,000 / 400

Mechanical advantage = 20

We want to have an acceleration of:

A = 1.5*g = 1.5*9.8m/s^2  = 14.7 m/s^2

When the rim is moving at 37m/s while spinning.

Now, in circular motion we have two accelerations.

Tangential acceleration, that is the one related to the change of speed, as we have a speed of 37m/s, we can assume that is constant, then the tangential acceleration is zero.

Centripetal acceleration, is the one related to the change in direction, is perpendicular to the velocity vector and is the one that allows the circular motion.

I suppose that in this problem we want to have a  centripetal acceleration of 14.7m/s^2

The equation for the centripetal acceleration is:

Ac = v^2/r

Where v = velocity and r = radius.

then we must solve:

14.7m/s^2 = (37m/s)^2/r

r = (37m/s)^2/14.7m/s^2 = 93.13 m