Imagine that you place a piece of copper with an initial temperature of 20°c in contact with some liquid water with an initial temperature of 100°c. assume that the physical system consisting of the copper and the water is thermally isolated from everything else; i. e., they can only exchange energy with each other.
a) sketch two three-phase diagrams, one for each substance, and mark the initial state for each one. explain in a sentence or two how you can tell if either substance will undergo a phase change during the process of coming to thermal equilibrium. you do not need to do any calculations.

Aforce of 34.5 newtons is applied to an object at an angle of 45 º with the horizontal. what is the force acting on the object in the horizontal direction?

According to newton's second law, when the same force is applied to two objects of different masses, a the object with greater mass will experience a great acceleration, and the object with less mass will experience an even greater acceleration, b. the object with greater mass will experience a smaller acceleration, and the object with less mass will experience a greater acceleration, c. the object with greater mass will experience a greater acceleration, and the object with less mass will experience a smaller acceleration, d. the object with greater mass will experience a small acceleration, and the object with less mass will experience an even smaller acceleration.

Which of the following is the main energy source for the sun? a. fission of hydrogen b. fusion of hydrogen c. fusion of helium d. fission of iron