Define Ohm's Law
1.
Answer
Ohm's Law states that the current flowing through a conductor is directly proportional to the voltage across it, provided the
temperature and physical conditions remain constant. This fundamental principle describes the relationship between voltage
(V), current (I), and resistance ( R ).
Voltage
(volts)
Resistance
(ohms)
Current (amps)
(FORMULA: V=IR )
Do bends in a wire affect its electrical resistance? Explain.
2.
Answer
No, bends in a wire do not affect its electrical resistance because the cross
-
sectional area and length
remain unchanged.
Why does the resistance of a conductor rise with temperature?
3.
Answer
The resistance of a conductor increases with temperature because higher temperatures cause increased
atomic vibrations, leading to more electron collisions and reduced conductivity. This relationship is
described by the temperature coefficient of resistance.
Why does the resistance of a conductor rise with temperature?
4.
Answer
The resistance of a conductor increases with temperature because higher temperatures cause increased
atomic vibrations, leading to more electron collisions and reduced conductivity. This relationship is
described by the temperature coefficient of resistance.
Explain the difficulties in testing whether the filament of a lighted bulb obeys Ohm's Law.
5.
Answer
The filament of a lighted bulb doesn't obey Ohm's Law perfectly. Initially, its resistance remains
relatively constant, but as it heats up, the resistance increases, causing the current to decrease. This
change in resistance with temperature makes it challenging to verify Ohm's Law.
Explain why the terminal potential difference of a battery decreases when the current drawn from
it is increased.
6.
Answer
The terminal potential difference decreases when the current drawn from the battery increases due to
the internal resistance of the battery. As the current increases, the voltage drop across the internal
resistance also increases, resulting in a decrease in the terminal potential difference available to the
external circuit.
State Kirchhoff's Laws.
7.
(power exhausted in watts)
Current Electricity Practice Quiz
New Section 1 Page 1
