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Title: GR9677.036
Post by: conantee on December 07, 2010, 12:14:20 AM
36. A lump of clay whose rest mass is 4 kilograms is traveling at three-fifths the speed of light when it collides head-on with an identical lump going the opposite direction at the same speed. If the two lumps stick together and no energy is radiated away, what is the mass of the composite lump?
(A) 4 \mbox{ kg}
(B) 6.4 \mbox{ kg}
(C) 8 \mbox{ kg}
(D) 10 \mbox{ kg}
(E) 13.3 \mbox{ kg}