electricty Flashcards
learn (25 cards)
Which of the following is neutral, without any charge?
atom
An atom is composed of protons, neutrons, and electrons, with the overall charge being neutral.
The unit used to measure electric current is:
amperes
Amperes are the standard unit for measuring electric current.
The instrument used to measure voltage is called:
a voltmeter
A voltmeter is specifically designed to measure electric potential difference.
What happens to the brightness of the first two light globes when a third globe is added in parallel?
they stay the same brightness
In a parallel circuit, additional globes do not affect the brightness of existing ones.
The resistance of a wire does NOT depend on the:
voltage applied across the wire
Resistance is dependent on material, length, and thickness, but not voltage.
Which of the following materials is an insulator?
rubber
Rubber is commonly known as an insulator, preventing the flow of electric current.
The supply voltage of the battery arrangement is:
A. 9 V
This indicates the voltage supplied by the battery in the arrangement.
Where should the switch be placed to turn on and off ALL the globes at once?
immediately to the left of globe B
This position allows control over the entire circuit.
How and where should the ammeter be connected to measure total current?
in series between globes C and D
An ammeter must be in series to measure current accurately.
How and where should the voltmeter be connected to measure total voltage?
in parallel, piggy-backing the battery
A voltmeter measures voltage and must be connected in parallel.
Which globes would stop glowing if globe A broke?
all globes
In a series circuit, if one globe breaks, it disrupts the entire circuit.
Which globes would stop glowing if globe C broke?
only globe D
In a series circuit, the break affects only the globes after the break point.
When globe C broke, what would happen to globe B?
Globe B would glow less brightly.
The current distribution changes, affecting brightness.
State the approximate current flowing through the globe when 2.5 V is applied across it.
0.02 A
This value is derived from the graph indicating current at that voltage.
Approximately what voltage causes a current of approximately 0.023 A to pass through it?
3 V
The relationship between current and voltage can usually be observed in a graph.
Predict the current when the battery is disconnected.
0 A
Disconnection of the battery results in no current flow.
Complete the following table: Quantity - Current, Unit - ______, Unit Symbol - A
Ampere
The unit for electric current is Ampere, often abbreviated as A.
Complete the following table: Quantity - Voltage, Unit - ______, Unit Symbol - V
Volt
The unit for electric voltage is Volt, often abbreviated as V.
Complete the following table: Quantity - Resistance, Unit - ______, Unit Symbol - Ω
Ohm
The unit for electrical resistance is Ohm, often represented by the symbol Ω.
What is the current in a 160V circuit if the resistance is 2Ω?
80 A
Calculated using Ohm’s Law: I = V/R.
What voltage is required to move 6A through 5Ω?
30 V
Calculated using Ohm’s Law: V = I * R.
What is the resistance of a circuit with three 1.5V batteries and running at a current of 5A?
0.9 Ω
Calculated using Ohm’s Law: R = V/I, where V = 4.5V.
Fill in the blanks: When David rubs the balloon against his hair, the balloon _____ his hair because _____ .
sticks to, static electricity has been produced
This demonstrates the principle of static electricity.
Is lightning caused by static electricity?
Yes
Lightning is a large-scale discharge of static electricity.
