Home › CBSE Class 11 (Science) › Physics › Laws of Motion › Friction between two surfaces in contact opposes:
Friction between two surfaces in contact opposes:
AAny motion of either body
BWeight of the upper body
CThe applied force always
DTheir relative motion
Answer & Solution
Correct answer: D. Their relative motion
Friction acts against impending or actual relative motion between surfaces, not against motion itself, which is why it can accelerate a box on a moving train.
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