مسائل في حفظ الطاقة و potential energy

بطرآنه العين · #1 14-05-2013, 10:51

السلام عليكم ورحمه الله وبركاته
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The two masses in the figure are released from rest with the 12 kg mass 2 m above the floor. use the energy conservation principle to find the speed with which the 12 kg mass hits the ground
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A 0.2 kg object is released from rest at point A on a track that is one-quarter of a circle with radius 1.6 m, as shown in the figure. It slides down and reaches point B with a speed of 4.8 m/s. Then it slides on a level surface a distance of 3 m until it comes to rest at point C.
a) How much work is done by friction on the package at it slides down the circular track from A to B
b) What is the coefficient of kinetic friction on the horizontal surface
c) What average power is produced by friction as the object moved from B to C
d) What instantaneous power is produced by friction at point B