Fundamentals of Electricity

A 220-V bulb draws a current of 10 A. How much charge in kilocoulombs will pass through the bulb in a two-hour period?

\(7.1 \times 10^{10}\) BTU is equal to______ Gcal.

The resistance of a coil of wire increases from 40 Ω at 10°C to 48.25 Ω at 60°C. Find the temperature coefficient at 0°C of the conductor material.

What is the resistance of 2,000 m of copper wire that has a resistivity of \(1.72 \times 10^{-8}\) Ω·m and a diameter of 4 mm?

The power required to produce a gain of 10dB over 4 w of original power is

Wavelength is the distance travelled by an electromagnetic wave during the time of one cycle. Given a wavelength of 12 meters, what is the frequency?

The resistances of the same length of aluminum and copper wires are found to be equal. Find the ratio of radii of aluminum to copper.

Find the amount of electrical energy expended in raising the temperature of 45 liters of water by 75°C. Assume a heater efficiency of 90%.

A Walkman has 4 – AA batteries. The combination has a capacity of 200 watt-sec. How long will it take to discharge if Walkman consumes 10 mA at 6 v?

A copper wire is drawn down such that its length is doubled but the volume remains the same, what is the new resistance of the wire?

A certain amount of fuel contains \(15 \times 10^{10}\) BTU of energy. What is the corresponding energy in kilocalories?

The resistance of a winding wire made up to copper is 25 ohms at 30°C. What is its resistance when it operates at a temperature of 75°C? Assume temperature coefficient at 20°C equals 0.004/°C.

A 40 m metallic conductor of cross-sectional area 1 mm² has a resistance of 12 Ω. Calculate the conductivity of the metal.

A car battery supplies 48 J of energy at 12 v over a certain period of time. Determine the charge moved during this period.

The current-carrying capacity of a copper wire having twice the diameter of another copper wire is ______________ as great.

\(10^{13}\) ergs/sec is equal to how many kW?

A coil of copper wire has a resistance of 5.46 Ω at 75°C. What will be its resistance at 25°C?

A copper conductor with a diameter of 0.10 inch has a resistance of 1 ohm per 1,000 ft. What is the resistance of 200 ft of copper wire with a diameter of 40 mils?

A transmission line cable consists of 26 strands of identical copper conductor, each 1.255 mm in diameter. The length of the cable is 10 km, but because of the twist of the strands, the actual length of each conductor is increased by 5%. If the resistivity of copper is \(1.72 \times 10^{-8}\) Ω·m, what is the resistance of the cable in ohms?

The diameter of a conductor is 0.064 inch. What is the area in circular mils?