The velocity and momentum of a moving body are 10,000 cm s⁻¹ and 10,000 g cm s⁻¹ respectively. The K.E will be
Correct answer: D. 5 x 10⁰ J
- A. 5 x 10⁷ J
- B. 5 x 10⁻² J
- C. 5 x 10⁸ J
- D. 5 x 10⁰ J
Explanation
Using KE = ½ p v with SI units: convert v = 10000 cm/s = 100 m/s, p = 10000 g·cm/s = 0.1 kg·m/s (better: p in SI = 10,000 g·cm/s = 0.1 kg·m/s), then KE = ½ p v = 0.5×0.1×100 = 5 J.Option D corresponds to 5 J (5×100 J).
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