Alight beam in air strikes the surface of water at an angle of 35° to the normal. when it enters the water it bends toward the normal, making an angle of 25.5° to it. the velocity of light in air is approximately 300,000 km/s. what is the approximate velocity of light in water? a. 77,000 km/s b. 225,000 km/s c. 278,000 km/s d. 341,000 km/s

Why is alternating current more effective at long–distance travel than direct current? a. the power lines are made out of conductors. b. transformers increase or decrease voltage as needed. c. the ac generator is more efficient. d. ac has lower voltage than dc.

(a) calculate the number of electrons in a small, electrically neutral silver pin that has a mass of 10.0 g. silver has 47 electrons per atom, and its molar mass is 107.87 g/mol. (b) imagine adding electrons to the pin until the negative charge has the very large value 1.00 mc. how many electrons are added for every 109 electrons already present

What are the north and south poles of a solenoid change with?