A body of mass 2 kg starts from rest and reaches 6 m per second in 3 s. The applied force is:
A4 N
B1 N
C6 N
D12 N
Answer & Solution
Correct answer: A. 4 N
1. Use v = u + at to find acceleration first.
2. Given u = 0, v = 6 m per second, t = 3 s, so a = (6 − 0) / 3 = 2 m per second squared.
3. Apply Newton's second law F = m·a.
4. F = 2 kg × 2 m per second squared = 4 N.
5. Option D wrongly multiplies mass by final velocity; A divides instead of multiplies.
_Source: Selina Concise Physics ICSE Class 9, Ch 3 'Laws of Motion' (aplustopper.com extract)_
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