A 60 kg body is pushed with just enough f

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A $60\, kg$ body is pushed with just enough force to start it moving across a floor and the same force continues to act afterwards. The coefficient of static friction and sliding friction are $0.5$ and $0.4$ respectively. The acceleration of the body is  ........ $m/{s^2}$

A

$6$

B

$4.9$

C

$3.92$

D

$1$

A $60\, kg$ body is pushed with just enough force to start it moving across a floor and the same force continues to act afterwards. The coefficient of static friction and sliding friction are $0.5$ and $0.4$ respectively. The acceleration of the body is  ........ $m/{s^2}$

Limiting friction $ = {\mu _s}R = {\mu _s}mg = 0.5 \times 60 \times 10 = 300\;N$ 

Kinetic friction $ = {\mu _k}R = {\mu _k}mg = 0.4 \times 60 \times 10 = 240\;N$ 

Force applied on the body $= 300 \,N$ and if the body is moving then, 

Net accelerating force = Applied force -Kinetic friction 

$⇒ ma = 300 - 240 = 60$

$\therefore a = \frac{{60}}{{60}} = 1\;m/{s^2}$