⚛️ Physics · Work, Energy and Power · NEET & JEE

A 1000 kg car runs under a constant engine power of 50 kW. When its speed is 10 m/s and the resistive force is 1000 N, its acceleration is:

Answer: 4 m/s 2.

A 1 m/s2
B 4 m/s2
C 2 m/s2
D 5 m/s2

Correct answer: B. 4 m/s2

Explanation: Driving force = P/v = 50000/10 = 5000 N. Net force = 5000 - 1000 = 4000 N. a = 4000/1000 = 4 m/s2.

As a pendulum swings, total mechanical energy (KE+PE) stays constant: at the highest points A and C, all energy is potential (zero speed); at the lowest point B, all of that energy has converted into kinetic energy (maximum speed).

Concept context

Work-energy theorem, potential energy, conservation of energy, collisions.

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A 1000 kg car runs under a constant engine power of 50 kW. When its speed is 10 m/s and the resistive force is 1000 N, its acceleration is:

Concept context

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