In this worksheet, we will practice calculating the kinetic energy of objects of different masses, moving at different velocities.

**Q2: **

A motorboat at rest on a lake has a mass of 665 kg. The motorboat then accelerates until it has a kinetic energy of 340 480 J. When the motorboat has accelerated, at what rate does it move toward a stationary boat that is directly in front of it?

**Q3: **

A hummingbird has a mass of 40 g. The hummingbird flies in a straight line between two flowers 18 m apart in a time of 12 s. What is the average kinetic energy of the hummingbird while flying between the flowers?

**Q4: **

An object has 75 J of kinetic energy and a mass of 1.5 kg. What is the velocity of the object?

**Q5: **

An object that has 9 J of kinetic energy is moving at 3 m/s. What is the mass of the object?

**Q6: **

An object with a mass of 1.25 kg has a velocity of 12 m/s. What is the object’s kinetic energy?

**Q7: **

An object’s kinetic energy when it moves at different velocities is shown in the table. What is the object’s mass in grams?

Velocity (m/s) | 1 | 2 | 3 | 4 | 5 |
---|---|---|---|---|---|

Kinetic Energy (J) | 0.1 | 0.4 | 0.9 | 1.6 | 2.5 |

**Q8: **

The quantity , the velocity of an object, is how much the object changes its displacement from a given position each second. The quantity is the kinetic energy of an object. Which of the following formulas correctly shows the relationship between , , and the mass of the object?

- A
- B
- C
- D
- E

**Q9: **

A motorcycle of mass 250 kg moving at 32 m/s has four times as much kinetic energy as a 640 kg mass car. What is the velocity of the car?

**Q10: **

An object’s kinetic energy when it moves at different velocities is shown in the graph.

What is the kinetic energy of the object when its instantaneous velocity is 2 m/s?

What is the kinetic energy of the object when its instantaneous velocity is 4 m/s?

What is the object’s mass?