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3 years ago

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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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If we have 10 wires of resistance R/10 each and connect them in parallel, the equivalent resistance is:

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Explanation:

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and, $\frac{n_{1}}{f(n - n_{1})} = \frac{1}{R_{1}} - \frac{1}{R_{2}}$

or, $f_{1} = \frac{fn_{1}(n - 1)}{(n - n_{1})}$

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Substituting the values in equation (1)

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Answer:

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- Other common electron withdrawing functional groups that will accelerate the Diels Alder reaction of dienophiles include aldehydes, ketones, and esters.

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- See attachment for graphical explanation.

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