Transcript Where do you think most of the energy from the fuel ends

Human
Body
Electric Shock
Multiple-Choice Questions
Physics and Astronomy Outreach Program at the University of British Columbia
Question 1
Electric Shock
Birds land on high voltage power lines,
Why don’t they get shocked?
a) The wires they land on are insulated.
b) They are not touching ground so there
is no potential difference across their bodies.
c) Birds have large resistance
Physics and Astronomy Outreach Program at the University of British Columbia
Question 1 solution
Electric Shock
Birds land on high voltage power lines,
Why don’t they get shocked?
a) The wires they land on are insulated.
b) They are not touching ground so there
is no potential difference across their bodies.
c) 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
Question 2
Electric Shock
If it is electrical current that hurts us, why
do the danger signs say ‘High Voltage’?
a) It is a convention established before
people understood what is
actually dangerous.
b) V= IR, as V increases, I increases
c) High currents can not occur unless
there are high voltages.
Physics and Astronomy Outreach Program at the University of British Columbia
Question 2 Solution
Electric Shock
If it is electrical current that hurts us, why
do the danger signs say ‘High Voltage’?
a) It is a convention established before
people understood what is
actually dangerous.
b) V= IR, as V increases, I increases
c) High currents can not occur unless
there are high voltages.
Physics and Astronomy Outreach Program at the University of British Columbia
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
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.
Question 4
Electric Shock
What is the main purpose of
the magnetic core?
a) To hold the sense
coil in place.
b) To magnify the Bfield inside the
sense coil.
c) To cause there
to be a B-field inside
the coil.
Question 4 Solution
Electric Shock
What is the main purpose of
the magnetic core?
a) To hold the sense
coil in place.
b) To magnify the Bfield inside the I
sense coil. B 
2 d
c) To cause there
to be a B-field inside
the coil.