beginning of content:
SAT Subject Test
A single resistor is connected to a battery as shown above. The current is
and the power dissipated as heat is
. The circuit is changed by doubling the emf of the battery while
is kept constant.
After the change, the power dissipated in is
Select an Answer
Correct Answer:
No
Correct Answer:
No
Correct Answer:
No
Correct Answer:
No
Correct Answer:
Yes
View Correct Answer
The correct answer is . The power
dissipated by a resistor is given by
, where
is the current in the resistor and
is the voltage across it. When used in combination with Ohm’s law, the power can also be written as , where
is the resistance. If the emf is doubled while
remains the same,
is quadrupled.
Question Difficulty:
hard