A horizontal force of magnitude 49.7 N pushes a block of mass 3.69 kg across a floor where the coefficient of kinetic friction is 0.561. (a) How much work is done by that applied force on the block-floor system when the block slides through a displacement of 2.66 m across the floor? (b) During that displacement, the thermal energy of the block increases by 38.9 J. What is the increase in thermal energy of the floor? (c) What is the increase in the kinetic energy of the block?
I can get A easy, W=Fxd, and I can get C easily after I get the total thermal energy, just the sum must equal W. But, how do I get the increase in the thermal energy of the floor (part B)?
EDIT: Help setting this one up would be great too.
Tarzan, who weighs 720 N, swings from a cliff at the end of a convenient vine that is 22 m long (Fig. 8-37). From the top of the cliff to the bottom of the swing, he descends by 3.1 m. The vine will break if the force on it exceeds 1260 N. What would the greatest force on the vine be during the swing?
I know it has something to do with potential energy=mg(change in y). But there are other factors I think. Does centripetal acceleration have anything to do with it?
I can get A easy, W=Fxd, and I can get C easily after I get the total thermal energy, just the sum must equal W. But, how do I get the increase in the thermal energy of the floor (part B)?
EDIT: Help setting this one up would be great too.
Tarzan, who weighs 720 N, swings from a cliff at the end of a convenient vine that is 22 m long (Fig. 8-37). From the top of the cliff to the bottom of the swing, he descends by 3.1 m. The vine will break if the force on it exceeds 1260 N. What would the greatest force on the vine be during the swing?
I know it has something to do with potential energy=mg(change in y). But there are other factors I think. Does centripetal acceleration have anything to do with it?
