A force acts for 20 s on a body of mass 20 kg, starting from rest, after which the force ceases and then body describes 50 m in the next 10 s. The value of force will be:
Solution
<p>$m = 20$ kg</p>
<p>$t = 20$ sec.</p>
<p>Acceleration $= {F \over {20}}$ m/s$^2$</p>
<p>$\therefore$ $v = u + at$</p>
<p>$v = 0 + \left( {{F \over {20}}} \right)(20)$</p>
<p>$= F$ ms$^{-1}$</p>
<p>Now for next 10 sec.</p>
<p>$S=ut$</p>
<p>$50=F(10)$</p>
<p>$F=5$</p>
About this question
Subject: Physics · Chapter: Laws of Motion · Topic: Newton's First Law
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