calculate the mass of steel if 28J of heat energy is needed to raise the temperature of the steel from 12 degrees celcius to 20 degrees celcius if the specific heat capacity of steel is 700J/kg degrees celcius???

The movement of electrons between atoms is called an

During a medieval siege of a castle, the attacking army uses a trebuchet to hurl heavy stones at the castle walls. if the trebuchet launches the stones with a velocity of at an angle of 50.0°, (a) how long does it take the stone to hit the ground? (b) what is the maximum distance that the trebuchet can be from the castle wall to be in range? (c) how high will the stones go? show all your work.

Metals are good conductors of electricity because they