Question Detail
Question
A 2 kg body is whirled in a horizontal circle of radius 1.5 m, making three complete revolutions every second. What is its linear speed?
Correct Answer
Option B is the correct answer.
Detailed Explanation
The frequency f = 3 rev/s. The period T = 1/f = 1/3 s. Using v = 2πR/T = 2πRf = 2π * 1.5 m * 3 rev/s = 2π * 1.5 * 3 = 9π m/s.
Hint
Linear speed v = 2πR / T, and T = 1/f. So v = 2πRf.