If it takes 3 s for a modern player to stop a DVD with a rot

If it takes 3 s for a modern player to stop a DVD with a rotational speed of 7500 rpm, what is the magnitude of the DVD\'s average rotational acceleration?

Select one:

a. 2500 rpm/s

b. 22,500 rpm/s

c. 150,000 rpm/s

d. 1,350,000 rpm/s

Solution

According to the given problem,

Acceleration= [V_f - V_f]/ time

a = [0 - 7500]/3

a = -7500/3

a = -2500.

|a| = 2500 rpm/s.

The -Ve sign means that the acceleration is against the direction of motion.

Answer is A.