Practice Problems
1. Two identical charges, each 7.6×10-5 C are separated by 0.11 m.
a) What is the force of one charge on the other?
b) Is this force an attractive or repulsive force?
2. A heating coil operates on 120 volts.
a) If it draws 15.0 A, find its resistance.
b) What is the power rating for this heating coil?
c) If the heating coil were operated for an hour, how much energy (in Joules) would be required?
3. Two resistors are connected in series with an 18 volt battery. The resistors have values of R1 = 20 Ω and R2 =9 Ω.
a) What is the current in this circuit?
b) What is the voltage across R1?
c) What is the voltage across R2?
4. A transformer has 500 turns in its primary (input) coil and 300 turns in its secondary (output) coil. The primary (input) coil is connected to 1200 V AC. What is the secondary (output) voltage?
5. How long does it take a beam of light to travel 1 foot in a vacuum?
Conversion factor: 1 meter = 3.28084 feet