Resistance and Ohm's Law

What is the formula to calculate resistance?

• V = I x R
• V = I / R
• R = I / V
• I = V x R

How does adding resistance affect a motor?

• Makes it spin more slowly
• Makes it spin faster
• Does not affect it
• Makes it stop working

What is resistance?

• The energy transferred by each unit of charge
• The amount of current in a circuit
• The measure of how difficult it is for current to flow
• The potential difference in a circuit

What happens to the current when the resistance in a circuit increases?

• It becomes negative
• It increases
• It decreases
• It stays the same

What is the effect of increasing resistance on the brightness of a lamp?

• Makes it less bright
• Does not affect it
• Makes it flicker
• Makes it brighter

What happens to resistance when more components are added in series?

• It decreases
• It becomes negative
• It stays the same
• It increases

What is the unit for voltage?

• Volts
• Amps
• Ohms
• Watts

What unit is resistance measured in?

• Watts
• Volts
• Amps
• Ohms

The current passing through a lamp is 0.5 A. If the voltage across the lamp is 9 V, what is the resistance?

• 4.5 Ω

• 18 Ω

• 0.05 Ω

• 2 Ω

What is the symbol for a resistor?

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