Gaokao Exam Physics: Mechanics and Kinematics 3

Question 1

A ball is thrown horizontally from a cliff of height 80 m with initial speed 20 m/s. How far from the base of the cliff does it land? (g = 10 m/s²)

Accepted Answer

80 m

Answer

40 m

Answer

160 m

Answer

20 m

Question 2

Two objects collide in a perfectly elastic collision on a frictionless surface. What is conserved?

Accepted Answer

Both momentum and kinetic energy

Answer

Only momentum

Answer

Only kinetic energy

Answer

Neither momentum nor kinetic energy

Question 3

A satellite orbits Earth at radius R with period T. If it moves to orbit at radius 4R, what is its new period?

Accepted Answer

8T

Answer

4T

Answer

2T

Answer

16T

Question 4

An object of mass 5 kg is pulled along a horizontal surface at constant velocity by a force of 20 N applied at an angle of 30° above horizontal. What is the coefficient of kinetic friction? (g = 10 m/s²)

Accepted Answer

≈ 0.40

Answer

0.50

Answer

0.20

Answer

0.25

Question 5

In simple harmonic motion (简谐运动), when is the acceleration of the oscillating object at maximum?

Accepted Answer

At the maximum displacement (amplitude position, turning points)

Answer

At the equilibrium position

Answer

When velocity is maximum

Answer

When kinetic energy is maximum

Question 6

A 10 kg block falls freely from rest. After 3 seconds, what is its kinetic energy? (g = 10 m/s²)

Accepted Answer

4500 J

Answer

450 J

Answer

300 J

Answer

900 J