Abead slides without friction around a loop_the_loop (see figure below). the bead is released from rest at a height h = 3.80r.

what is its speed at point a? (use the following as necessary: the acceleration due to gravity g, and r.)
v=__

how large is the normal force on the bead at point a if its mass is 4.10 grams?
magnitude=__
direction=downward

Aman throws a football straight into the air. as it rises, it slows down. which type of energy is the football gaining?

Boxing gloves are padded to lessen the force of a blow. (a) calculate the force exerted by a boxing glove on an opponent’s face, if the glove and face compress 7.50 cm during a blow in which the 7.00-kg arm and glove are brought to rest from an initial speed of 10.0 m/s. (b) calculate the force exerted by an identical blow in the gory old days when no gloves were used and the knuckles and face would compress only 2.00 cm. (c) discuss the magnitude of the force with glove on. does it seem high enough to cause damage even though it is lower than the force with no glove?

The man of mass m1 and the woman of mass m2 are standing on opposite ends of the platform of mass m0 which moves with negligible friction and is initially at rest with s = 0. the man and woman begin to approach each other. derive an expression for the displacement s of the platform when the two meet in terms of the displacement x1 of the man relative to the platform.