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2 years ago

A boy and his dog are running. The dog has a mass of 20kg and the boy has a mass of 45kg.

Physics

1 answer:

Ad libitum [116K]2 years ago

4 0

Answer:

Explanation:

mass of boy =m1=45 kg

mass of dog =m2=20kg

the speed of boy=3 m/s

the speed of dog =3 m/s

K.E of boy

K.E=1/2mv²

K.E=1/2(45)(3)²

K.E=202.5 J

K.E of dog

K.E=1/2mv²

K.E=1/2(20)(3)²

K.E=90 J

now the new speed of dog is 6 m/s

therefore new K.E of dog is

K.E=1/2(20)(6)²

K.E=360 j

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