1. Multiple-Choice Questions
Human
Body
Electric Shock
Multiple-Choice Questions
Physics and Astronomy Outreach Program at the University of British Columbia

2. Question 1 Birds land on high voltage power lines,
Electric Shock
Question 1
Birds land on high voltage power lines,
Why don’t they get shocked?
The wires they land on are insulated.
They are not touching ground so there
is no potential difference across their bodies.
Birds have large resistance
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3. Question 1 solution Birds land on high voltage power lines,
Electric Shock
Question 1 solution
Birds land on high voltage power lines,
Why don’t they get shocked?
The wires they land on are insulated.
They are not touching ground so there
is no potential difference across their bodies.
Birds have large resistance
In V=IR, V refers to a potential difference across
the resistor(bird). Birds normally only touch the
lines at one potential.
Physics and Astronomy Outreach Program at the University of British Columbia 3

4. Question 2 If it is electrical current that hurts us, why
Electric Shock
Question 2
If it is electrical current that hurts us, why
do the danger signs say ‘High Voltage’?
It is a convention established before people understood what is
actually dangerous.
V= IR, as V increases, I increases
High currents can not occur unless there are high voltages.
Physics and Astronomy Outreach Program at the University of British Columbia 4

5. Question 2 Solution If it is electrical current that hurts us, why
Electric Shock
Question 2 Solution
If it is electrical current that hurts us, why
do the danger signs say ‘High Voltage’?
It is a convention established before people understood what is
actually dangerous.
V= IR, as V increases, I increases
High currents can not occur unless there are high voltages.
Physics and Astronomy Outreach Program at the University of British Columbia 5

6. Question 3
Electric Shock
If you touched both the hot wire from an outlet and the neutral wire simultaneously, would the GFCI turn off ?
a) Yes
b) No

7. Question 3 Solution
Electric Shock
If you touched both the hot wire from an outlet and the neutral wire simultaneously, would the GFCI turn off ?
a) Yes
b) No
The magnetic flux through the sense
coil stays at zero. No change in flux
is detected compared to normal
operating conditions. 7

8. Question 4 What is the main purpose of the magnetic core?
Electric Shock
What is the main purpose of
the magnetic core?
To hold the sense
coil in place.
b) To magnify the B-field inside the sense coil.
c) To cause there
to be a B-field inside
the coil. 8

9. Question 4 Solution What is the main purpose of the magnetic core?
Electric Shock
What is the main purpose of
the magnetic core?
To hold the sense
coil in place.
b) To magnify the B-field inside the sense coil.
c) To cause there
to be a B-field inside
the coil. 9