Jill does twice as much work as Jack does and in half the time. Jill's power output is A) the same as Jack's power output. B) one-fourth as much as Jack's power output. C) one-half as much as Jack's power output. D) twice Jack's power output. E) four times Jack's power output.

True or false graphs must include scales that increase by the same amount

As you are trying to move a heavy box of mass m, you realize that it is too heavy for you to lift by yourself. there is no one around to , so you attach an ideal pulley to the box and a massless rope to the ceiling, which you wrap around the pulley. you pull up on the rope to lift the box. use g for the magnitude of the acceleration due to gravity and neglect friction forces. once you have pulled hard enough to start the box moving upward, what is the magnitude f of the upward force you must apply to the rope to start raising the box with constant velocity? express the magnitude of the force in terms of m, the mass of the box.

If angle "a" is 25°, angle "b" is: a) equal to angle c b) less than angle c c) greater than angle c