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3 years ago

The instant before a tennis racquet hits a 0.057 kg tennis ball, the velocity of the ball is 55 m/s west. The instant after

Physics

1 answer:

Wewaii [24]3 years ago

5 0

Answer: 6700m/s^2 E

Explanation:

Given the following :

Velocity of ball before being hit by a racquet = initial velocity(u) = 55m/s W

Velocity of the ball after being hit = final Velocity (v) = 45m/s E

Time of contact between ball and racquet (t) = 1.5 × 10^-2

The acceleration of a body is the change in Velocity of a body with time. It given by:

Acceleration (a) = [final Velocity(v) - initial velocity(u)] / time(t)

The westward direction is towards the left and thus Velocity takes a negative value, similarly, if it's towards the right, Velocity takes a positive value.

Therefore,

a = [45 - (-55)] / 1.5×10^-2

a = [45 + 55] / 0.015

a = 100 / 0.015

a = 6666.6666 m/s^2

a = 6700m/s^2 E

Since the value of acceleration is positive, the direction is towards the East (acceleration is in the direction of the ball's final Velocity).

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