Explain with a suitable example whether or not the force of friction always acts opposite to the direction of motion.
(N/A) The statement that the force of friction always acts opposite to the direction of motion is not entirely correct. While friction generally opposes the relative motion between two surfaces,it can sometimes act in the direction of motion.
Example: Consider a person walking. When a person walks,they push the ground backward with their foot. According to Newton's third law,the ground exerts an equal and opposite force on the foot in the forward direction. This forward force is the static friction acting on the foot,which enables the person to move forward. In this case,the force of friction acts in the direction of motion.
Example: Consider a person walking. When a person walks,they push the ground backward with their foot. According to Newton's third law,the ground exerts an equal and opposite force on the foot in the forward direction. This forward force is the static friction acting on the foot,which enables the person to move forward. In this case,the force of friction acts in the direction of motion.
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