18) From an initial rest state, suddenly block B is let go and it starts going down. What is the acceleration of block A? A) aa = 9.81 m/s^2 B) a < 9.81 m/s^2 C) a > 9.81 m/s^2 D) aa = 0
2kg = 0.2
10 kg
19) A boy is swinging back and forth in the playground. Which of the following statements describe the potential and kinetic energy balance correctly when he swings between points A and C? A) T = Tc = 0, and V = V = 0 B) T = Tc = max, and V = V = max C) Ta = Tc = max, and Vg = V = 0 D) Ta = V = 0, and Tg = V = max E) None of the above
20) A ball with a weight of 20 N is moving along a smooth surface. If the velocity at point A is given as 3.13 m/s, what is the normal force applied by the surface on the ball? A) 10 N C) 20 N B) 30 N D) 40 N E) None of the above
p = 2m
21) While a 1000 kg car was traveling 50 m/s, the brakes are applied to slow it down to 10 m/s. What is the total work done on the car? A) 120,000 J B) 1200 kJ C) -120,000 J D) -1200 kJ E) None of the above
22) A constant force F is applied for 6 seconds to change the particle's velocity from v to V2. Determine the force F if the particle's mass is 6 kg. A) (17.3 i) N C) (17.3 i) N B) (20 i + 17.3 j) N D) (-20 i - 17.3 j) N E) None of the above
V = 10 m/s @ t = 8 s
v = 20 m/s @ t = 2 s
23) Impulse by an external force applied on a rigid body can cause change in A) Linear momentum C) Angular momentum B) No change in momentum D) Both Linear and Angular momentum E) None of the above
