Newton’s Second Law corrected the old belief that force is needed to maintain motion. This idea came from the philosopher:
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प्रश्न
A motorcycle of mass 100 kg is running at 10 ms−1. If its engine develops an extra linear momentum of 2000 Ns, calculate the new velocity of a motorcycle.
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उत्तर
Mass of motor cycle = m = 100 kg
Velocity of motor cycle = v1= 10 ms−1
Momentum of motor cycle = mv1 = 100 × 10 = 1000 Ns
When engine develops an extra linear momentum of 2000 Ns
Then total momentum of motor cycle = 1000 + 2000 = 3000 Ns
Let v2 = new velocity of the motorcycle.
Total momentum of motor cycle = mv2
3000 = 100 × v2
v2 = `3000/100` = 30 ms−1
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