Physics Exam

1. Which one of the following is correct about the four basic forces in nature?

A. Weak nuclear force keeps the electrons in their orbit around a nucleus.
B. Strong nuclear force is short-range force that holds protons and neutrons together inside a nucleus.
C. Gravitational force is attractive force that acts on the scale of the atomic nucleus.
D. Electromagnetic force is the weakest of all the forces in nature.

2. Which of the following is correct about impulse?

A. The impulse is smaller than change of momentum which caused by the applied force.
B. Impulse due to a force exerted for a short time is equal to impulse due to the same force exerted for a long time.
C. During momentum change final momentum of an object is along the impulse on the object.
D. The direction of the impulse is in the same direction to change in the momentum of the object.

3. A person walked 10 m in a direction 53° North of East, 10 m North, and finally 20 m in a direction 37° North of West. The magnitude of the person's displacement is

A. 20.0 m.
B. 40.0 m.
C. 31.6 m.
D. 30.0 m.

4. Which of the following pair of vectors is collinear?

A. G = 2î + 3ĵ and F = 3î + 2ĵ
B. E = −î + ĵ and F = 3î − 3ĵ
C. A = 2î + 3ĵ and B = − 4î + 6ĵ
D. C = î + ĵ and D = î − ĵ

5. A ball is thrown vertically upward with 12 m/s from the ground. Its speed when the ball is 4.0 m above the ground is

A. 12 m/s.
B. 10 m/s.
C. 15 m/s.
D. 8 m/s.

6. An object is projected at angle θ from the horizontal with initial velocity v₀. Which one of the following expressions represents the relationship between maximum height, h_max, and range of the projectile, R?

A. R = 4h_max/tan θ
B. R = 2h_max/tan θ
C. R = 4h_max tan θ
D. R = h_max tan θ / 2

7. A 0.5 kg block moving with an initial speed of 5.0 m/s slides 2.5 m on a rough horizontal surface before coming to rest. The coefficient of kinetic friction is

A. 0.4.
B. 0.1
C. 0.3.
D. 0.5.

8. A 0.2 kg ball is kicked from the ground at 16 m/s in a direction making an angle θ above the horizontal. Neglecting air resistance, the magnitude of velocity of the ball when it is 3.0 m from the ground is

A. 16 m/s.
B. 14 m/s.
C. 2 m/s.
D. 7 m/s.

9. A small ball of mass m tied to a rope of length l is moving along a vertical circle about a point O as shown in the figure.

If A, B, C, and D are points on the path, then which one of the following is correct about the force exert on the ball at these points?

A. At point B, the radial force is equal to the gravitational force on the ball.
B. At point A, the radial force is in opposite direction to the gravitational force on a ball.
C. At point D, the radial force is equal to the tension on the rope.
D. At point C, the radial force and the tension on the rope are in opposite direction.

10. The angular speed of a disk rotating about its axis increases by 2000 rad/s in a time interval of 3.0 s. If the moment of inertia of the disk is 0.6 kg·m², what is the average torque on the disk?

A. 400 Nm
B. 6000 Nm
C. 1200 Nm
D. 670 Nm

11. The gauge pressure at a point in a fluid at rest is defined as

A. the atmospheric pressure difference between sea level and the local area at which the fluid exists.
B. the pressure difference between the absolute pressure and the atmospheric pressure.
C. the sum of absolute pressure and atmospheric pressure.
D. the actual pressure at a given point relative to absolute vacuum.

12. How do we use manometer to measure pressure of a given gas? We use in such a way that

A. the gauge pressure in a fluid in the open end equals the gas pressure in closed tube.
B. the gauge pressure equals the atmospheric pressure.
C. the pressure at the surface of open end manometer is the same as the gas pressure in closed tube.
D. the principle of the hydrostatic equilibrium is considered to measure the pressure of unknown gas.

13. Consider two balls A and B are projected with the same velocity, v₀ at angles θ₁ and θ₂, respectively, 0 < θ₁ < 45° and 45° < θ₂ < 90°. Which one of the following statements is correct about the motion of the balls?

A. The two balls cover equal ranges when θ₁ + θ₂ = 90°.
B. Both balls have equal speed at their respective maximum height.
C. Ball A takes longer time than ball B to reach its maximum height.
D. The range of ball A is smaller than its maximum height.

14. A car initially traveling at speed of 20 m/s undergoes a constant deceleration of magnitude 1.5 m/s². If the radius of each tire is 0.3 m, how many revolutions does each tire make, without slipping, before the car comes to rest?

A. 133.33 rev
B. 44.44 rev
C. 70.77 rev
D. 444.4 rev

15. A constant tangential force is applied on a rim of uniform solid disk of mass m = 50 kg and radius r = 0.5 m. If the angular speed of the disk changes by 1 rev/s within 2.0 s, what is the magnitude of the torque produced by the force? (moment of inertia of disk I= mr²/2 )

A. 8.25 Nm
B. 3.125 Nm
C. 19.6 Nm
D. 39.3 Nm

Physics Exam

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