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3 years ago

If a car skids to a stop in 3.8s while undergoing a uniform acceleration of -9.55 m/s2, what is the car’s velocity?

Physics

1 answer:

Lapatulllka [165]3 years ago

3 0

Answer:

36.29 m/s

Explanation:

We know from theory that $v= v_0 +a\Delta t$ . Let's replace the value we know in our equation and solve for the only value left.

$0 = v_0 - 9.55 \cdot 3.8 \\ v_0 = 9.55 \cdot 3.8 = 36.29 m/s$

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$q_1 = 12\cdot 10^{-9} C\\q_2 = -23\cdot 10^{-9} C\\r = 0.41 m$

Substituting these values into the equation, we find the force

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When the two spheres are connected, the charge distribute equally over the two spheres (since they are identical, they have same capacitance), so each sphere will have a charge of

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So the electrostatic force between the two spheres will now be

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and the positive sign means the force is repulsive, since the two spheres have same sign charges.

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