A class is performing an experiment to keep an ice cube solid as long as possible. Which students actions could be a source of error in this experiment A. Maria checked her ice cube every half hour and forgot to reseal the container she put the ice cube in

B. Jody used a different experimental design than Carlos used

C. Carey repeated the experiment with three different ice cubes

D. Jerrie measured the ice cube before it started to melt

Which simple machine is not part of this compound machine? a. lever b. pulley c. inclined plane d. wheel and axle

Which statement correctly describes a step-up transformer? a. it increases the amount of electric energy available. b. it increases the voltage of an electric current. c. it changes direct current into alternating current. d. it has more loops of wire in its primary coil.

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?