Electric Current Flashcards
(26 cards)
What is ultimately responsible for electric shock, a high current or a high voltage?
High current
What happens to the current in a circuit when you add a resistor?
The current stops or slows down
What happens to the brightness of light bulb, if you add another lightbulb in series?
Then light bulbs light will dim
What happens to the current through a light bulb, if you add another lightbulb in series?
It share the current with the other bulb.
What happens to the brightness of light bulb, if you add another lightbulb in parallel?
The brightness stays the same
What happens to the current through a light bulb, if you add another lightbulb in parallel?
The bulbs will each have their own current
What causes a material to be “magnetic”?
If a large percentage of atoms which it is comprised.
What is electric potential energy?
Energy possessed by electric charges by virtue of their position an electrostatic field
What is the SI unit of electrical potential energy?
Johle
What is electric potential?
The difference in electrical charge between two points in a circuit expressed in volts
What is the SI unit of electric potential?
Voltage
What is electric current?
Rate at which charges pass a given point
What is the SI unit of electric current?
Ampere
What is electrical resistance?
The opposition to the flow of electric change
What is the SI unit for electrical resistance?
Ohm(Ω)
What is the difference between alternating current and direct current?
AC is current that changes direction charges oscillate back and forth
Which has more resistance a thick wire or a thin wire?
Thin wire
Which has more resistance a long wire or a short wire?
Long wire
Calculate the current through a wire with a 50 V potential difference and a 10 Ω resistance.
I=V/I=50V/10Ω=5 V/Ω or 5A
Calculate the resistance of a wire with a 100V potential difference and a 20A current.
R=V/I=100V/20A=5 V/A or 5Ω
Calculate the voltage across a wire with a 40 A current and a 5 Ω resistance.
V=IR=40A5Ω=200V
What kind of electricity is caused by friction?
Static Electricity is caused by friction.
How are charged particles in matter affected when two objects are rubbed together?
All matter is made up of tiny particles that have electric charges. Some of these particles have a positive charge. Other particles have a negative charge. Rubbing two objects together may cause some of the negative charges to rub off one object. The charges move to the second object. This gives the second object a greater negative charge than the first object.
How is current electricity produced?
Current electricity is produced when negative charges move along a path.