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 particle of mass 0.3 kg is subjected to a force F = −kx with k = 15 N/m. What will be its initial acceleration if it is released from a point x = 20 cm?
योग
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उत्तर
Displacement of the particle from the mean position, x = 20 cm = 0.2 m
k = 15 N/m
Mass of the particle, m = 0.3 kg
Acceleration, \[a = \frac{\left| F \right|}{m}\]
\[\Rightarrow a = \frac{kx}{m} = \frac{15\left( 0 . 2 \right)}{0 . 3} = \frac{3}{0 . 3} = 10 m/ s^2\]
So, the initial acceleration when the particle is released from a point x = 20 cm is 10 m/s2.
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