Download Electric Current I.C.E. Current Within an oscilloscope a beam of

Electric Current I.C.E.
Current
Within an oscilloscope a beam of electrons has a current of 2.3 × 10-5 A. The magnitude of the charge on an electron is
1.602 × 10-19 C. How long does it take for 9.45 × 1014 electrons to strike the screen?
A refrigerator draws 49.0 A when it starts up. If the start-up time is 0.69 s, how much charge passes a cross-sectional
area of the circuit in this time?
A total charge of 3.4 mC passes through a cross-sectional area of a copper wire in 4.5 s.
a) What is the current in the wire?
b) How many electrons pass through the cross-sectional area in 20 s?
c) If the number of charges that pass through the cross-sectional area during the given time interval doubles,
what is the resulting current?
A net charge of 54 mC passes through the cross-sectional area of a wire in 4 s.
a) What is the current in the wire?
b) How many electrons pass the cross-sectional area in 8.0 min?
Ohm’s Law
A toaster is connected to a voltage of 123 V and has a resistance of 62Ω . What is the current in the toaster?
An air hockey table is connected to a potential difference of 123 V and has a resistance of
39 Ω. What is the current in the air hockey table?
The current in a microwave oven is 6.78 A. If the resistance of the oven’s circuitry is 17.6 , what is the potential
difference across the oven?
0.40 A of current flow through a resistor when it is connected to 160 V. What is the current in this same resistor if the
operating potential difference is 377 V?
Power
A heat lamp with a power rating of 1040W operates on a household circuit of 129 V. What is the resistance of the wire
that makes up the heating element of the lamp?
An industrial fan is operated by applying a potential difference of 54.0 V across a titanium wire of total resistance 4.00
Ω.
a) Find the current in the wire.
b) Find the power rating of the fan.
My electric tooth brush is rated at 0.72 W when connected to 2.40 V battery. What is the resistance of this device?
Several appliances are supplied with a potential difference of 372 V and are operated
continuously for a 24 h period. How much energy is used if the appliance is a 45.0 W stereo?
Assume electrical energy costs $0.080 per kW·h, and that appliances have a potential
difference across them of 125 V.
a) Calculate the cost of running a 60.0 W stereo for 24 h.
b) Calculate the cost of running an electric oven that draws 22.0 A of current for 24 h.
c) Calculate the cost of running a television with a resistance of 75.0 for 24 h.
How much of energy is used if the appliance is an electric oven that draws 70.0 A of current?