Linear momentum Knowledge-Based Practice

Questions

1. 1.

   An object of constant mass moves along a straight line. If the magnitude of its linear momentum is doubled, by what factor does its kinetic energy increase?

   • A) 4
   • B) 2
   • C) 8
   • D) 16
2. 2.

   An object moving along a straight line has a kinetic energy of 200 J and a linear momentum of magnitude 40 kg·m/s. What is the mass of the object?

   • A) 2.0 kg
   • B) 4.0 kg
   • C) 5.0 kg
   • D) 8.0 kg
3. 3.

   A constant net force acts on an object moving along a straight line, changing the magnitude of its linear momentum from 20 kg·m/s to 65 kg·m/s over a time interval of 5.0 s without changing its direction. What is the magnitude of the net force acting on the object?

   • A) 4.0 N
   • B) 9.0 N
   • C) 13 N
   • D) 17 N
4. 4.

   Object X has a mass of 2.0 kg and moves along a straight line at a speed of 12 m/s. Object Y has a mass of 6.0 kg and has the same magnitude of linear momentum as object X. What is the speed of object Y?

   • A) 36 m/s
   • B) 12 m/s
   • C) 4.0 m/s
   • D) 1.5 m/s
5. 5.

   Two carts on a straight, horizontal track travel toward each other: a 3.0 kg cart moves east at 4.0 m/s, and a 2.0 kg cart moves west at 3.0 m/s. What is the magnitude of the total linear momentum of the two-cart system?

   • A) 1.0 kg·m/s
   • B) 6.0 kg·m/s
   • C) 12 kg·m/s
   • D) 18 kg·m/s
6. 6.

   A 1.5 kg toy car travels at a constant speed of 4.0 m/s around a circular horizontal track. Which statement correctly describes the linear momentum of the car?

   • A) Its magnitude is 6.0 kg·m/s, and its direction remains constant.
   • B) Its magnitude continuously changes, and its direction remains constant.
   • C) Its magnitude continuously changes, and its direction continuously changes.
   • D) Its magnitude is constant at 6.0 kg·m/s, but its direction continuously changes.
7. 7.

   An object of mass 2.5 kg moves along a straight line with a constant acceleration of 2.0 m/s². If the object starts from rest, what is the magnitude of its linear momentum after 6.0 s?

   • A) 5.0 kg·m/s
   • B) 15 kg·m/s
   • C) 30 kg·m/s
   • D) 90 kg·m/s
8. 8.

   A 0.20 kg ball moving horizontally at 15 m/s strikes a wall and rebounds along the same horizontal line with a speed of 10 m/s. What is the magnitude of the change in the linear momentum of the ball?

   • A) 5.0 kg·m/s
   • B) 1.0 kg·m/s
   • C) 3.0 kg·m/s
   • D) 2.0 kg·m/s
9. 9.

   A 0.5 kg object moves due north at 6.0 m/s, and a 0.8 kg object moves due east at 5.0 m/s. What is the magnitude of the total linear momentum of the two-object system?

   • A) 1.0 kg·m/s
   • B) 3.5 kg·m/s
   • C) 5.0 kg·m/s
   • D) 7.0 kg·m/s
10. 10.

    An object of mass $m$ has kinetic energy $E$ and a linear momentum of magnitude $p$. What is the magnitude of the linear momentum of a second object of mass $4m$ that has the same kinetic energy $E$?

    • A) $\frac{1}{4}p$
    • B) $\frac{1}{2}p$
    • C) $2p$
    • D) $4p$

Answers and step-by-step solutions appear after you finish the test.