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4 years ago

An object moving with a speed of 21 m/s and has a kinetic energy of 140 J, what is the mass of the object.

Physics

2 answers:

alexira [117]4 years ago

7 0

Answer:2940

Explanation:

Masteriza [31]4 years ago

7 0

Answer:

0.635 kg

Explanation:

Recall that Kinetic energy is defined as:

K.E. = (1/2) mv²,

where

K.E = Kinetic energy = given as 140J

m = mass (we are asked to find this)

v = velocity = given as 21 m/s

Substituting the above values into the equation:

K.E. = (1/2) mv²

140 = (1/2) m (21)² (rearranging)

m = (140)(2) / (21)²

m = 0.635 kg

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Answer:

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Part Two

Answered above. 240 watts.

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