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[align=center]بسم الله الرحمن الرحيم

السلام عليكم ورحمة الله وبركاته

عندي اسئلة ومعاي اجابات وابي اتأكد من صحتها والتأكد من كونها نموذجيه

اسئله بسيطه but just in case

الاسئله بالترتيب

A bowling ball sits at rest.A nother ballrolls down a lane at constant speed . Wich ,if either. is in equilibrium?
defend your answer

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How does the direction of a friction force compare with the velocity of a sliding object??

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A hockey puck slides across the ice at a constant velocity . Is it mechanical equilibrium? why or why not??

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if you push horizeontally on acrate that contains your new disk and it slides across the floor , slightly gaining speed, how does the friction acting on the crate compare with your push??


الاجوبه بالترتيب

Bath balls, the one at rest and the one rolling down at constant speed are at equilibrium.

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Friction force is opposite in direction of the velocity of the sliding object.

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It is mechanical equilibrium because the force of friction is equal and opposite to the force with which the puck was pushed.

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Since the crate is gaining speed (accelerating) it means that there is a net force acting on the crate in the direction of the travel. Your push is larger than the friction force and they are opposite in direction.

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