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3 years ago

12

The potential energy of a catapult was completely converted into kinetic energy by releasing a small stone with a mass of 20 gra

ms. The velocity of the stone when it reached the target was 15.0 meters/second. What was the value of the kinetic energy of the stone when it reached the target?

2 answers:

vaieri [72.5K]3 years ago

6 0

Answer: 2.25 J

Explanation: Kinetic energy is the energy possessed by an object by virtue of its motion.

$K.E=\frac{1}{2}\times mv^2$

m= mass of object= 20 g = 0.02 kg (1 kg= 1000 g)

v= velocity of object= 15 m/s

$K.E=\frac{1}{2}\times 0.02\times 15^2=2.25kgm^2s^{-2}=2.25J$

$(1J=1kgm^2s^{-2})$

DerKrebs [107]3 years ago

4 0

1,000 grams = 1 kilogram
20 grams = 0.02 kilogram

Kinetic energy = (1/2) (mass) x (speed)²

(1/2) (0.02) x (15)² =

(0.01) x (225) = 2.25 joules

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