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A lorry of mass 4000 kg is travelling at a speed of 4.0m/s.

A car has a mass of 1000kg.The kinetic energy of the car is equal to the kinetic energy of the lorry.
What is the speed of the car?

A) 2.0m/s B) 4.0m/s C) 8.0m/s D)16.0m/s
PLS ANWSER​

User Js Lim
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1 Answer

3 votes

Answer:

8 ms⁻¹

Step-by-step explanation:

Kinetic energy is the energy possessed by a moving object solely due to its motion.

You can get the K.E. of an object using the equation,

K.E. = (1/2)mv²

So you get, for lorry,

K.E. = (1/2)4000×4² -----------(1)

for car,

K.E. = (1/2)1000×v²---------------(2)

(1)=(2)

(1/2)4000×4² = (1/2)1000×v²

y these two equations, we get, v = 8 ms⁻¹

User Vmank
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