Awave has a period of 0.25 seconds. the frequency of this wave is

Acharge of 8.4x10^-4 c moves at an angle of 35 degrees to a magnetic field that has a field strength of 6.7x10^-3 t. if the magnetic force is 3.5 x10 ^-2 n, how fast is the charge moving?

In a hydrogen molecule there are a total of four charges, 2 protons in the two nuclei, and 2 electrons. how many unique charge-pairs are there (without double counting)?

Acapacitor is storing energy of 3 joules with a voltage of 50 volts across its terminals. a second identical capacitor of the same value is storing energy of 1 joule. what is the voltage across the terminals of the second capacitor?