A 50g lead bullet (sp. heat = 0.02) is at 30^(@)C. It is fired vertically upwards with a speed of 840 m s^(-1). On returning to the starting level it strikes the ice cake at 0^(@)C. How much ice is melted ? (L.H. of ice 80 cal/gm):

A 50g lead bullet (sp. heat = 0.02) is at 30^(@)C. It is fired vertica

1.	A 50g lead bullet (sp. heat = 0.02) is at 30^(@)C. It is fired vertically upwards with a speed of 840 m s^(-1). On returning to the starting level it strikes the ice cake at 0^(@)C. How much ice is melted ? (L.H. of ice 80 cal/gm):
Answer» 52.875 g 5.2875 g 528.75 8 None of these. Solution :Here `(1)/(2) mv^(2) =(1)/(2) xx50xx10^(-3)xx(840)^(2)` `=4200` cals. Also heat given by bullet to cool to `0^(@)C mc theta =50xx0.02 xx30=30` cals TOTAL heat =4230 =ML or `M=(4230)/(80)=52.875 g`. `THEREFORE` Correct choice is (a).

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A 50g lead bullet (sp. heat = 0.02) is at 30^(@)C. It is fired vertically upwards with a speed of 840 m s^(-1). On returning to the starting level it strikes the ice cake at 0^(@)C. How much ice is melted ? (L.H. of ice 80 cal/gm):

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