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2 years ago

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Two particles A and B start simultaneously from a Point P with velocities 20 m/s and 30 m/s respectively. A and B move with acce

leration equal in magnitude but opposite in direction. When A overtakes B at Q, its velocity is 30 m/s. The velocity of B at Q :

1 answer:

zysi [14]2 years ago

6 0

Answer:

<u>20 m/s</u>

Explanation:

<u>Given</u>

u(A) = 20 m/s
u(B) = 30 m/s
acceleration equal in magnitude but opposite in direction

<u>Solving</u>

Velocity of A at Q = 30 m/s
From, P to Q, <u>Δv(A) = 30 - 20 = +10 m/s</u>
Therefore, velocity of B at Q will be decreased by 10 as it is equal in magnitude but opposite in direction to A
Δv(B) = v(B at Q) - u(B at P)
-10 m/s = v(B at Q) - 30 m/s
v(B at Q) = 30 - 10 = <u>20 m/s</u>

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