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3 years ago

Can anyone please help me with the steps

Physics

1 answer:

KIM [24]3 years ago

3 0

Answer:

A) v_average = - 10 km / h, B) v = 1.6 m / s, v = 17.6 m / s

Explanation:

A) the average speed is the average speed of a body, if we assume that the direction of going up the hill is positive

v₁ = 40 km / h

v₂ = - 60 km / h

the average speed is

v_average = $\frac{v_1 + v_2}{2}$

v_average = ( 40 - 60)/2

v_average = - 10 km / h

B) in this case they indicate the acceleration a = 3.2 m / s² and the velocity vo = 9.6 m / s

i) the speed for 2.5 s above

v = v₀ + a t

as the time is earlier

t = - 2.5 s

we substitute

v = 9.6 - 3.2 2.5

v = 1.6 m / s

ii) the velocity for a subsequent time of 2.5 s

t = 2.5 s

we substitute

v = 9.6 + 3.2 2.5

v = 17.6 m / s

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2) Yes

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4) Equal and opposite

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6) Repulsive

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$e=1.6\cdot 10^{-19}C$

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Charge Q exerts an electric force on charge 5Q, and we can call this action force. At the same time, charge 5Q exerts an electric force on charge Q (reaction force), and according to Newton's 3rd law, the two forces are equal and opposite.

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