Niels bohr had a theory about the structure of an atom. which part of his theory has been proven wrong? a. an atom is mostly empty space. b. atoms are rearranged in chemical reactions. c. the nucleus is made up of protons and neutrons. d. electrons travel in prescribed orbits around the nucleus.

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.

Which is an example of an exothermic process?

Which of the following will cause an induced current in a coil of wire? the constant field of the earth passing through the coil a magnet resting near the coil a magnet being moved into or out of the coil a wire carrying a constant current near the coil