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If an object with a mass of #12 kg # changes speed from #1 m/s# to #2 m/s#, by how much does its kinetic energy change?

Answer 1

Olivia Askew

The kinetic energy increases by #6"J"#

Kinetic energy has the following expression:

#KE=1/2mv^2#

The initial #KE# is :

#1/2xx12xx1=6"J"#

Following the acceleration, this changes to:

#1/2xx12xx2=12"J"#

So you can see that the #KE# has increased from 6 to 12J which is an increase in 6J.

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Answer 2

Olivia Askew

To calculate the change in kinetic energy, you can use the formula:

ΔKE = 0.5 * m * (vf^2 - vi^2)

Where: ΔKE = Change in kinetic energy m = Mass of the object (12 kg) vf = Final velocity (2 m/s) vi = Initial velocity (1 m/s)

ΔKE = 0.5 * 12 * ((2)^2 - (1)^2) ΔKE = 0.5 * 12 * (4 - 1) ΔKE = 0.5 * 12 * 3 ΔKE = 6 * 3 ΔKE = 18 joules

So, the change in kinetic energy is 18 joules.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.