Which statement best describes a physical change?
O Changes can occur to certain chemical properties of the substance, but the overall shape of the substance will remain the
same.
O Changes can occur to certain physical properties of the substance, but the overall shape of the substance will remain the
same
O Changes can occur to physical properties of a substance, but the chemical composition of the substance remains the
same
O Changes can occur to chemical properties of a substance, but the chemical composition of the substance remains the
same.

Ten students stand in a circle and are told to make a transverse wave. what best describes the motion of the students? each student bumps the shoulder of his or her neighbor. at the exact time, all students take a step to the right. the students skip clockwise, going in a circular motion. one at a time, each student lifts his or her hands up and then down.

Acamcorder has a power rating of 20 watts. if the output voltage from its battery is 9 volts, what current does it use?

16. a brave but inadequate rugby player is being pushed backward by an opposing player who is exerting a force of 800 n on him. the mass of the losing player plus equipment is 90.0 kg, and he is accelerating at 1.20m/s2 size 12{1 "." "20"" m/s" rsup { size 8{2} } } {} backward. (a) what is the force of friction between the losing player’s feet and the grass? (b) what force does the winning player exert on the ground to move forward if his mass plus equipment is 110 kg? (c) draw a sketch of the situation showing the system of interest used to solve each part. for this situation, draw a free-body diagram and write the net force equation.