Circular Motion (OCR A Level Physics): Exam Questions

A scientist states: “The radius of the orbit of the Earth around the Sun is decreasing by a small amount each year, however, the time period of the orbit remains constant.”

Which row of the table is correct if the statement is true?

A metal ball of mass 0.55 kg is swung round on the end of a string so that the ball moves in a horizontal circle of radius 1.5 m.

The ball travels at a constant speed of 6.2 m s⁻¹

What is the time taken (seconds) for the string to turn through an angle of 200°?

Saturn and its moon may be considered to be isolated in space with their masses concentrated at their centres. The orbit of the moon around Saturn is circular with a radius of 4.84 × 10⁵ km. The period of the orbit is 29.3 days.

What is the angular velocity of the Moon in its orbit around Saturn?

Two pendulums, P and Q, are released from rest and oscillate in simple harmonic motion with the same period .

Pendulum P passes through its equilibrium position, moving in the positive direction.

Pendulum Q passes through its equilibrium position, moving in the positive direction a time later.

What is the phase difference between the motion of the two pendulums?

A particle of mass travels in a circular path of radius with a constant frequency .

What is the magnitude of the centripetal force acting on the particle?