Dynamics — Quiz 1

Questions in this quiz (10)

1. A 1200 kg car accelerates from 15 m/s to 25 m/s on a level road. Determine the net work done on the car.

   • 180 kJ
   • 240 kJ
   • 300 kJ
   • 420 kJ

2. A vehicle engine exerts a constant driving force of 650 N while the vehicle maintains a constant speed of 10 m/s. What is the power output of the engine?

   • 4.5 kW
   • 6.5 kW
   • 7.5 kW
   • 9.0 kW

3. A rotating wheel has a mass moment of inertia of 6.0 kg·m² about its central axis. A constant torque of 18 N·m is applied. Determine the angular acceleration.

   • 1.5 rad/s²
   • 2.0 rad/s²
   • 3.0 rad/s²
   • 4.5 rad/s²

4. Car A travels east at 70 km/h while Car B travels north at 50 km/h. Determine the magnitude of the velocity of Car A as observed from Car B.

   • 86 km/h
   • 94 km/h
   • 100 km/h
   • 120 km/h

5. Two blocks with masses of 12 kg and 8 kg are connected by a light cord passing over a frictionless pulley. Assuming g = 9.81 m/s², determine the acceleration when released from rest.

   • 1.96 m/s²
   • 2.45 m/s²
   • 3.92 m/s²
   • 0.98 m/s²

6. A worker lifts a 60 kg load vertically through a height of 15 m. Assuming g = 9.81 m/s², calculate the change in gravitational potential energy.

   • 7350 J
   • 8829 J
   • 9810 J
   • 735 J

7. A simple pendulum consists of a bob attached to a 1.2 m long cord. The pendulum is released from rest at 30° from the vertical. Assuming g = 9.81 m/s², determine the speed at the lowest point.

   • 2.00 m/s
   • 1.78 m/s
   • 2.50 m/s
   • 3.10 m/s

8. An electric motor develops a torque of 120 N·m while rotating at 180 rpm. Determine the power output.

   • 2.26 kW
   • 3.14 kW
   • 2.85 kW
   • 3.77 kW

9. In a pulley system, block A moves downward 2 m while block B moves upward 4 m. If block A has a velocity of 3 m/s downward, what is the velocity of block B?

   • 6 m/s upward
   • 4 m/s upward
   • 3 m/s upward
   • 1.5 m/s upward

10. A car travels along a curved path defined by $$y=0.08x^2$$ After traveling $$180\ m$$, the car attains a speed of $$18\ m/s$$ and has a tangential acceleration of $$1.8\ m/s^2$$. The magnitude of the total acceleration $$\left(m/s^2\right)$$ of the car at this instant is most nearly:

    • $$1.6$$
    • $$1.8$$
    • $$2.8$$
    • $$3.4$$