Ablock that has a mass m = 500 g is hanging at rest on a light string. a projectile with a mass m = 15 g moving horizontally with a velocity of 255 m/s strikes m and sticks in it. the block and its projectile swing up. how high does the center of mass rise?

2.8m

Explanation:

Convert to metric:

500g = 0.5 kg

15g = 0.015 kg

Assuming elastics collision, we could use the law of momentum conservation to calculate the speed of black and projectile post-collision V:

mv = (M + m)V

This would make the system moves up, which convert its kinetic energy to potential energy. By the law of energy conservation when the mass reaches its highest point (aka speed = 0)

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