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प्रश्न
A body of mass 2 kg is at rest. What should be the magnitude of force which will make the body move with a speed of 30 m/s at the end of 1 s ?
उत्तर
The body gains speed 30 m/s in 1 s. So, the acceleration is,
a = 30/1 = 30 m/s2
Mass, m = 2 kg
Force = mass × acceleration
Force = m × a
= 2 × 30 = 60
The magnitude of force = 60 N
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