Kinetic Energy

Concept Quizzes

Kinetic Energy Warmup
Understanding Kinetic Energy
Kinetic energy of an object
Kinetic energy lost in inelastic collisions

Challenge Quizzes

Kinetic Energy: Level 2-4 Challenges

Kinetic energy of an object

A $14\text{ kg}$ object initially at rest starts to fall freely. If air resistance is negligible, what is the object's kinetic energy after $0.5$ seconds?

The gravitational acceleration is $g=10\text{ m/s}^2.$

140\text{ J}

70\text{ J}

175\text{ J}

490\text{ J}

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by Brilliant Staff

What is the kinetic energy of a $6\text{ kg}$ object moving at $10\text{ m/s}?$

300\text{ J}

600\text{ J}

60\text{ J}

120\text{ J}

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by Brilliant Staff

A car of mass $1900\text{ kg}$ is traveling at $28\text{ m/s}$ on a street that has a speed limit of $20\text{ m/s}.$ The driver spots a police car and reduces its speed to match the speed limit. How much kinetic energy did the car lose?

364.8\text{ kJ}

729.6\text{ kJ}

121.0\text{ kJ}

243.0\text{ kJ}

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by Brilliant Staff

A $10\text{ kg}$ object, $A$ , travels at $6\text{ m/s},$ and a $6\text{ kg}$ object, $B$ , travels at $10\text{ m/s}.$

Find the ratio $\text{K.E.}_A/\text{K.E.}_B$ .

3:5

25:9

9:25

5:3

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by Brilliant Staff

Recently, a meteor impacted Russia. The estimate of the meteor's size was $10~\mbox{tons}$ and it was estimated to have entered the earth's atmosphere at a speed of $14,600~\mbox{m/s}$ . What was the total kinetic energy of such a meteor $\si{\joule}$ as it entered the atmosphere?

Details and assumptions

One ton is $907~\mbox{kg}$ .

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by Brilliant Staff