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प्रश्न
An object of mass 100 kg is accelerated uniformly from a velocity of 5 ms−1 to 8 ms−1 in 6 s. Calculate the initial and final momentum of the object. Also, find the magnitude of the force exerted on the object.
उत्तर
Mass of the body = 100kg
The initial velocity of the body = 5m/s
The final velocity of the body = 8m/s
Time = 6s
The initial momentum of the body = Mass × Initial velocity of the object
= 100 × 5
= 500 kgm/s
Momentum of the body later = 100 × 8
= 800 kgm/s
Force (F) = `"Momentum change"/"Time"`
= `(800-500)/6`
= `300/6`
= `100/2`
Force = 50N
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