Mark and David are loading adentaical cement blocks on to David\'s pickup truck
Channel: Doubtnut
Date: 2020-01-19

Mark and David are loading adentaical cement blocks on to David\'s pickup truck .Mark lifts his block straight up from the ground to the truck , whereas David slides his block up a ramp contining frictionless roles .Which statement is true about the work done on the block - Earth system?