Asap!
a 40 kg-skier starts at the top of a 12-meter high slope. at the bottom, she is traveling 10 m/s. how much energy does she lose to friction? a. she doesn't lose any because mechanical energy is always conserved.
b.4,704 j
c. 2,000 j
d.2,704 j

Which is the correct symbol for an isotope of iodine with 53 protons and 78 neutrons?

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.

Auniform crate c with mass mc is being transported to the left by a forklift with a constant speed v1. what is the magnitude of the angular momentum of the crate about point a, that is, the point of contact between the front tire of the forklift and the ground