Question

A 0.75kg block is tied at one end of a rope, 1.5m in length. The block is swung around a vertical circle and rotates four times each minute. (A)what is the centripetal acceleration of the block?

Answer 1

I found: `a_c=v^2/r=0.26m/s^2`

Explanation:

The centripetal acceleration is given as:
`a_c=v^2/r`
The block completes `4` rotations each minute so it describes `4*2pi` radians each `60` seconds giving and angulra velocity of:
`omega=(4*2*pi)/60=0.42(rad)/s`;
The corresponding linear velocity is:
`v=omegar=0.42*1.5=0.63m/s`.
So finally:
`a_c=v^2/r=(0.63)^2/1.5=0.26m/s^2`