Abattery charger is connected to a dead battery and delivers a current of 3.5 a for 4 hours, keeping the voltage across the battery terminals at 16 v in the process. how much energy is delivered to the battery?

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.)