As per your syllabus, a bullet of mass 50 g at 200 m/s emerges from plywood with 10% of initial KE. The emergent speed is closest to which value?
A63.2 m/s
B20 m/s
C6.3 m/s
D100 m/s
Answer & Solution
Correct answer: A. 63.2 m/s
syllabus Ex 5.4: K_i = (1/2)(0.05)(200)² = 1000 J. K_f = 100 J
We have ⇒ v_f = √(2 K_f/m).
So ⇒ v_f = √(4000) ≈ 63.2 m/s.
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