Quiz 12:

1. Which of the following is not a correct statement.

• A. If the net force acting on an object is zero, then its momentum is conserved.
• B. The impulse acting on an object is equal to the change of momentum of the object.
• C. During a completely elastic collision, some of the kinetic energy of the colliding objects is converted to heat energy.
• D. Momentum of colliding objects is always conserved.
• E. If colliding objects are treated as a single system, then the net force acting on the system is zero.

2. Calculate the momentum of an object of mass 12 kg if its kinetic energy is 10 J.

• A. 6.074 kg m ⁄ s
• B. 2.76 kg m ⁄ s
• C. 15.492 kg m ⁄ s
• D. 19.739 kg m ⁄ s
• E. 10.725 kg m ⁄ s

3. After a bullet of mass 0.035 kg is fired into a ballistic pendulum of mass 2 kg, the bullet is embedded in the pendulum and the pendulum rose to a height of 0.05 m. Calulate the speed of the pendulum just after the collision.

• A. 1.113 m ⁄ s
• B. 0.657 m ⁄ s
• C. 1.251 m ⁄ s
• D. 1.538 m ⁄ s
• E. 0.99 m ⁄ s

4. After a bullet of mass 0.04 kg is fired into a ballistic pendulum of mass 5 kg, the bullet is embedded in the pendulum and the pendulum rose to a height of 0.2 m. Calulate the speed with which the bullet was fired into the ballistic pendulum.

• A. 249.467 m ⁄ s
• B. 206.405 m ⁄ s
• C. 284.6 m ⁄ s
• D. 447.152 m ⁄ s
• E. 472.685 m ⁄ s

5. An object of mass 3 kg going to the right with a speed of 27 m ⁄ s collides with a(n) 16 kg object at rest. If the collision is completely elastic, calculate the speed of the 16 kg object after collision.

• A. 9.955 m ⁄ s
• B. 4.752 m ⁄ s
• C. 7.466 m ⁄ s
• D. 8.526 m ⁄ s
• E. 1.831 m ⁄ s

6. An object of mass 11 kg going to the right with a speed of 30 m ⁄ s collides with a(n) 12 kg object going in the same direction with a speed of 17 m ⁄ s. If the collision is completely elastic, calculate the speed of the 12 kg object after collision.

• A. 3.175 m ⁄ s
• B. 29.435 m ⁄ s
• C. 8.134 m ⁄ s
• D. 47.148 m ⁄ s
• E. 17.698 m ⁄ s

7. An object of mass 5 kg going to the right with a speed of 15 m ⁄ s collides with a(n) 14 kg object going to the left with a speed of 17 m ⁄ s. If the collision is completely elastic, calculate the speed of the 14 kg object after collision.

• A. -0.028 m ⁄ s
• B. -0.093 m ⁄ s
• C. -0.121 m ⁄ s
• D. -0.267 m ⁄ s
• E. -0.158 m ⁄ s

8. An object of mass 3 kg going to the right with a speed of 25 m ⁄ s collides with a(n) 14 kg object at rest. After collision the 3 kg object moves with a speed of 17 m ⁄ s making an angle of 40 degree with the horizontal-right. Calculate the x-component of the velocity of the 14 kg object after collision.

• A. 2.567 m ⁄ s
• B. 0.771 m ⁄ s
• C. 3.836 m ⁄ s
• D. 1.454 m ⁄ s
• E. 2.143 m ⁄ s

9. An object of mass 15 kg going to the right with a speed of 26 m ⁄ s collides with a(n) 2 kg object at rest. After collision the 15 kg object moves with a speed of 17 m ⁄ s making an angle of 70 degree with the horizontal-right. Calculate the y-component of the velocity of the 2 kg object after collision.

• A. -163.191 m ⁄ s
• B. -210.487 m ⁄ s
• C. -92.791 m ⁄ s
• D. -183.88 m ⁄ s
• E. -119.811 m ⁄ s

10. An object of mass 3 kg going to towards north with a speed of 26 m ⁄ s collides with a(n) 26 kg object going east with a speed of 35 m ⁄ s. After collision the 3 kg object moves with a speed of 12 m ⁄ s making an angle of 30 degree with the horizontal-right. Calculate the magnitude and direction of the velocity of the 26 kg object after collision.

• A. 32.05 m ⁄ s, 3.906 deg
• B. 33.88 m ⁄ s, 4.431 deg
• C. 41.824 m ⁄ s, 3.259 deg
• D. 33.88 m ⁄ s, 3.906 deg
• E. 30.492 m ⁄ s, 4.431 deg