The spring-mounted 0.84-kg collar A oscillates along the horizontal rod, which is rotating at the constant angular rate rad/s. At a certain instant, r is increasing at the rate of 610 mm/s.
If the coefficient of kinetic friction between the collar and the rod is 0.61, calculate the friction force F exerted by the rod on the collar at this instant.

Aforce of 9.00 newtons acts at an angle of 19.0 to the horizontal. what is its component in the horizontal direction?

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 slope of a velocity time graph over any interval of time gives the during that interval