A 75-kg person, starting from rest, sleds down a slide 40. m high hill reaching the bottom with a speed of 18 m/s. Calculate a) the PE at the top,

b) the KE at the bottom of the hill,

c) and finally, the thermal energy that was generated in the process.

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

According to an observer on earth, planet x is stationary. maria and samir depart earth on their spaceships at the same time, each flying at 0.5c. maria flies toward planet x and samir flies in the opposite direction. according to maria, her voyage to planet x takes 9 years. how many years does maria's voyage take according to samir?

It may seem strange that the selected velocity does not depend on either the mass or the charge of the particle. (for example, would the velocity of a neutral particle be selected by passage through this device? ) the explanation of this is that the mass and the charge control the resolution of the device--particles with the wrong velocity will be accelerated away from the straight line and will not pass through the exit slit. if the acceleration depends strongly on the velocity, then particles with just slightly wrong velocities will feel a substantial transverse acceleration and will not exit the selector. because the acc