If the current through a bulb in a series circuit is 0.4 A and the potential difference across the bulb is 3 V then what is the resistance? Offering 25 points!

An electron moving at 5.06 103 m/s in a 1.23 t magnetic field experiences a magnetic force of 1.40 10-16 n. what angle does the velocity of the electron make with the magnetic field? there are two answers between 0° and 180°. (enter your answers from smallest to largest.)

A15 ohm resistor and a 25 ohm resistor are connected in a series to a 60 volt battery. what is the power used by each device

Conventional hot-water heaters consist of a tank of water maintained at a fixed temperature. the hot water is to be used when needed. the drawback is that energy is wasted because the tank loses heat when it is not in use, and you can run out of hot water if you use too much. some utility companies are encouraging the use of on-demand water heaters (also known as flash heaters), which consist of heating units to heat the water as you use it. no water tank is involved, so no heat is wasted. a typical household shower flow rate is 2.50 gal/min (9.46 l/min ) with the tap water being heated from 51.0 ˚f (10.6 ˚c) to 120 ˚f (48.9 ˚c) by the on-demand heater.what rate of heat input (either electrical of from gas) is required to operate such a unit, assuming that all the heat goes into the water?