Kiểm tra bài cũ - Kinematics of circular motion

The period in uniform circular motion is:

• the time the object moves.

• the time the object takes to complete one half revolution.

• the number of revolutions per second.

• the time the object takes to complete one revolution.

In uniform circular motion:

• the velocity vector is always zero.

• the velocity vector is always directed inward.

• the velocity vector has constant magnitude and is tangent to the path.

• the velocity vector is always directed toward the center of the path.

In uniform circular motion, the quantity measured by the number of revolutions per unit of time is called:

• velocity.

• frequency.

• speed.

• period.

The Vinasat I geostationary satellite has a rotation period of T = 24 hours. What is the value closest to the frequency of this satellite?

• 1.16 × 10⁻⁵ Hz

• 4.2 × 10⁻² Hz

• 4.2 × 10⁻³ Hz

• 1.16 × 10⁻⁴ Hz

An object moves in uniform circular motion with an angular speed of w = 2 rad/s. In 3 seconds, the angle swept out with the center of the circle is:

• 9 rad.

• 18 rad.

• 3 rad.

• 6 rad.

A person is driving a car on the road at a speed of v = 54 km/h. The radius of the car wheel is r = 28.5 cm. The rotation frequency of the wheel is:

• 5.48 Hz.

• 5.95 Hz.

• 8.38 Hz.

• 8.55 Hz.

A point moves uniformly along a circular path with a radius of r = 60 cm. It completes 300 revolutions in one minute. The speed of the point is:

• 4π m/s.

• 6π m/s.

• 6 m/s.

• 4 m/s.

Match the following pairs

• vận tốc

• Speed v

• bán kính

• Period T

• chu kì

• Radius r

• tốc độ góc

• Frequency f

• tần số

• Angular speed w

Match the following pairs

• lực ma sát

• Tangent

• lực hấp dẫn

• Gravitational force

• lực căng dây

• Frictional force

• vuông góc

• Perpendicular

• tiếp tuyến

• Tension T