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3 years ago

6

In being served, a tennis ball is accelerated from rest to a speed of 42.1 m/s. The average power generated during the serve is

2920 W. Assuming that the acceleration of the ball is constant during the serve, find the force acting on the ball.

1 answer:

hoa [83]3 years ago

8 0

Answer:

Force F = 69.35 N

Explanation:

given data

Ball Initial speed u = 0

Ball Final speed v = 42.1 m/s

average power generate = 2920 W

solution

Power generate is express as

P= $\frac{W}{t}$ ..............1

here W is work done and t is time

and work w = F × d

so

P= $\frac{Fd}{t}$

and we know speed v = $\frac{d}{t}$

so here

Power P = F × v

put here value and we get force

Force F = $\frac{2920}{42.1}$

Force F = 69.35 N

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Answer:

This question is about matching each definition with its correct term. Please find the term matched with their appropriate definition below.

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3 years ago

A 873-kg (1930-lb) dragster, starting from rest completes a 401.4-m (0.2509-mile) run in 4.945 s. If the car had a constant acce

Delvig [45]

To solve this problem it is necessary to apply the kinematic equations of motion.

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And the velocity can be expressed as,

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Where,

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For our case we have that there is neither initial position nor initial velocity, then

$x= at^2$

With our values we have $x = 401.4m, t=4.945s$ , rearranging to find a,

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3 years ago

Determine the amount of work done by the applied force when a 87 N force is applied to move a 15 kg object a horizontal

elena-s [515]

Answer:

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2 years ago

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3 years ago