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What is the mass of an object if it is moving at a speed of 10 m/s and has 400 J of kinetic energy?

User Eliasdx
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Answers:

8 kg

Step-by-step explanation:

Kinetic Energy = (mass × velocity × velocity) ÷ 2

We know that Kinetic Energy = 400 J and velocity = 10 m/s.

KE = (m × v × v) ÷ 2

400 J = (m × 10 m/s × 10 m/s) ÷ 2

400 J = m × 50 m^2/s^2

To find the mass you will divide 400 J and 50 m^2/s^2.

m = 8 kg

You can also check it if it gives you 400 J.

KE = (m × v × v) ÷ 2

KE = (8 kg × 10 m/s × 10 m/s) ÷ 2

KE = 400 J

So this means that the mass is 8 kg. I know that it is a bit confusing, but when you do J (joules) ÷ m^2/s^2 = kg (kilograms). Hope this helps, thank you !!

User Luke Collins
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