11. [Walker2 9.P.010.] A 0.50 kg croquet ball is initially at rest on the grass. When the ball is struck by a mallet, the average force exerted on it is 235 N. If the ball's speed after being struck is 2.6 m/s, how long was the mallet in contact with the ball? (in miliseconds)(adsbygoogle = window.adsbygoogle || []).push({});

F = ma

235 = 0.50 * a

a = 235 / 0.5

a = 470

v = at

2.6 = 470 t

t = 2.6 / 470

t = 0.00553191489361702 s

t = 5.53 ms

I got this correct according to the online grading system, but if they were picky about significant figures wouldn't I have done?:

t = 0.00553191489361702 s

2.6 is the value with the least amount of significant digits with 2, therefore

t = 0.0 s

t = 0 ms

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# Homework Help: Significant figures question

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