The wheel of a railway carriage is 4 ft in diameter and makes 6 revolution per second, how fast is the trains going? `(pi=3.14)`

The wheel of a railway carriage is 40cm in diameter and makes 6 revolutions in a second, how fast is the train going?

The wheel of a railway carriage is 40 cm in diameter and makes 7 revolutions in a second, find the speed of train.

The wheel of an engine of 300 cm in circumference makes 10 revolutions in 6 seconds. What is the speed of the wheel (in km/h)?

If the wheel of the engine of a train 4(2)/(7) metres in circumference makes 7 revolutions in 4 seconds,then the speed ( in km/hr) of the train is (a) 27 (b) 28 (c) 29 (d) 30

A pendulum suspended from the roof of a railway carriage travelling at a speed v mis round a curve of radius 'a' metres makes n oscillations per second. If the same pendulum makes n_1 oscillations per second when the carriage is stationary, what is the value of v_2 ?

if OP makes 4 revolutions in one second,the angular velocity in radians per second is?

A one kg stone attached to the end of a 60 cm chain is revolving at the rate of 3 revolutions/second. It is found that after 30 second, it makes only one revolution per second. What is the mean torque ?

The wheels of the locomotive of a train are 2.1 m in radius. They make 75 revolutions in one minute. Find the speed of the train in km per hour.