A spring is 17.5 cm long when it is lying on a table. One end is then attached to a hook and the other end is pulled by a force that increases to 27.5 N, causing the spring to stretch to a length of 19.3 cm. For related problem-solving tips and strategies, you may want to view a Video Tutor Solution of Work done on a spring scale.

What is the force constant of this spring?
Express your answer in newtons per meter.

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?