A 5 meter long ramp is inclined at an angle of 37 degrees above the horizontal. A box that weighs 18 N slides down it. If the coefficient of kinetic friction is uk=0.29, what is the magnitude of the acceleration of the box down the ramp?|

What are similarities and differences between refraction, reflection, diffraction and absorption?

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.

You charge a parallel-plate capacitor, remove it from the battery, and prevent the wires connected to the plates from touching each other. when you increase the plate separation, what happens to the following quantities?