PLEASE HELP ANSWER THIS QUESTION ! 1) Joel has tied a 0.25 kg stone to the end of a 0.85 m rope. As he spins the rock above his head, Joel exerts a 45.5 N centripetal force to keep the stone in circular motion. Based on this information, what is the period, T, of the stone's circular motion.

Energy flows from the producer level to the level. is called

Amichelson interferometer operating at a 600 nm wavelength has a 3.02-cm-long glass cell in one arm. to begin, the air is pumped out of the cell and mirror m2 is adjusted to produce a bright spot at the center of the interference pattern. then a valve is opened and air is slowly admitted into the cell. the index of refraction of air at 1.00 atm pressure is 1.00028.how many bright-dark-bright fringe shifts are observed as the cell fills with air?

Resistivity of a material is the resistance of a cm long sample of the material of 1 cm2 cross-sectional area.