Bob, of mass m, drops from a tree limb at the same time that esther, also of mass m, begins her descent down a slide. they both start at the same height above the ground. if there is friction on the slide, which of the following is true about their kinetic energies as they reach the ground? a. esther's kinetic energy is greater than bob's. b. bob's kinetic energy is greater than esther's. c. they have the same kinetic energy. d. the answer depends on the shape of the slide. e. the answer depends on the length of the slide.

What is the relationship between the wavelength of a wave and it's energy?

Two technicians are discussing a resistance measurement between the can-h and can-l wires. technician a says this measurement should be done with the ignition switch in the "run" position. technician b states that a measurement of 0 ohms indicates an open in the network. which technician is correct?

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.