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3 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]3 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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Answer:

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Given that

q1 = +7.7 µC is at x1 = +3.1 cm

q2 = -19 µC is at x2 = +8.9 cm

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$E_1=9\times 10^9\times \dfrac{7.7\times 10^{-6}}{0.031^2}\ N/C$

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$E_2=9\times 10^9\times \dfrac{19\times 10^{-6}}{0.089^2}\ N/C$

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The direction will be negative direction.

As we know that electric filed line emerge from positive charge and concentrated at negative charge.

Now

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distance for charge 2 will become =8.9-5.5 = 3.4 cm

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