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Sahay Sir > Question Answers > NCERT Exemplar Class 11 > Physics > Chapter 5 - Work, Energy and Power > A person trying to lose weight (dieter) lifts a 10 kg mass, one thousand times, to a height of 0.5 m 1000 times. Assume that the potential energy lost each time she lowers the mass is dissipated. (a) How much work does she do against the gravitational force? (b) Fat supplies 3.8 ×10^7 J of energy per kilogram which is converted to mechanical energy with a 20% efficiency rate. How much fat will the dieter use up?

A person trying to lose weight (dieter) lifts a 10 kg mass, one thousand times, to a height of 0.5 m 1000 times. Assume that the potential energy lost each time she lowers the mass is dissipated. (a) How much work does she do against the gravitational force? (b) Fat supplies 3.8 ×10^7 J of energy per kilogram which is converted to mechanical energy with a 20% efficiency rate. How much fat will the dieter use up?

A molecule in a gas container hits a horizontal wall with speed 200 m s^−1 and angle 30 degree with the normal A person trying to lose weight (dieter) lifts a 10 kg mass and rebounds with the same speed. Is momentum conserved in the collision ? Is the collision elastic or inelastic ? one thousand times