PHYS 1420: College Physics II
Fall 2009
Quiz 05 (12989): Ohm’s Law
Quiz 05 (12990): Ohm’s Law
1.
True or false: Two bulbs in series are each brighter
than a single bulb, when connected to the same 3V
power source.
1.
True or false: Two bulbs in series are each dimmer
than a single bulb, when connected to the same 3V
power source.
2.
True or false: If one bulb in a series circuit burns out,
the remaining bulbs are unaffected.
2.
True or false: If one bulb in a series circuit burns out,
the remaining bulbs also go out.
3.
True or false: If one bulb in a parallel circuit burns
out, the remaining bulbs are unaffected.
3.
True or false: If one bulb in a parallel circuit burns
out, the remaining bulbs also go out.
4.
True or false: Two bulbs in series will draw more
current than two bulbs in parallel when connected to
the same 3V power supply.
4.
True or false: Two bulbs in series will draw less
current than two bulbs in parallel when connected to
the same 3V power supply.
5.
True or false: If the power supply remains in the HI
setting, the maximum current produced is sufficient
to permanently damage the current probe.
5.
True or false: If the power supply remains in the HI
setting, the maximum current produced is sufficient
to permanently damage the current probe.
6.
The 68Ω resistor has a tolerance of ±5%. What would
be the smallest value of measured resistance that
would be within tolerance? Answer with three sig
figs.
6.
The 51Ω resistor has a tolerance of ±5%. What would
be the smallest value of measured resistance that
would be within tolerance? Answer with three sig
figs.
Rmin = (0.95)(68Ω) = 64.6Ω
7.
€
8.
€
Rmin = (0.95)(51Ω) = 48.5Ω
When a 51Ω resistor is wired in series with a 68Ω
resistor, what equivalent resistance would you expect?
Answer with three sig figs.
7.
R = R1 + R2 = 51Ω + 68Ω = 119Ω
When a 20Ω resistor is wired in series with a 51Ω
resistor, what equivalent resistance would you expect?
Answer with three sig figs.
R = R1 + R2 = 20Ω + 51Ω = 71Ω
€
When two 51Ω resistors are wired in series, what
slope would you expect on the voltage vs current
graph?
A) 0Ω
B) 25.5Ω
C) 51Ω
D) 102Ω
E) 2600Ω
8.
€
When two 68Ω resistors are wired in series, what
slope would you expect on the voltage vs current
graph?
A) 0Ω
B) 34Ω
C) 68Ω
D) 136Ω
E) 4600Ω
A resistor is marked with brown,
green, red, and silver bands.
A resistor is marked with red,
green, brown, and silver bands.
9.
9.
What is the resistance in Ohms?
R = (15) ×100Ω = 1500Ω
R = (25) ×10Ω = 250Ω
10. What is the percent tolerance
of this resistor?
€
What is the resistance in Ohms?
10. What is the percent tolerance
of this resistor?
R ± 10%
11. What does the break, or
discontinuity, in the voltage vs
current curve for the light bulb mean?
€ A) It means that the person increasing the voltage
stopped for a moment, then continued to turn
the knob.
B) It means that the bulb is faulty. A properly
functioning bulb should have a perfectly linear
graph, just like the resistors.
C) The bulb starts with a lower resistance. When
the filament starts to glow, the resistance
increases because of the heat generated.
D) The bulb starts with a higher resistance. When
the filament starts to glow, it reduces the
resistance and the slope of the curve decreases.
E) What discontinuity? The graph starts perfectly
linear, and remains perfectly linear over the
entire range of voltage tested.
Section 12989
€
R ± 10%
11. What does the break, or
discontinuity, in the voltage vs
current curve for the light bulb mean?
A)
B)
C)
D)
E)
€ The graph starts perfectly
What discontinuity?
linear, and remains perfectly linear over the
entire range of voltage tested.
The bulb starts with a lower resistance. When
the filament starts to glow, the resistance
increases because of the heat generated.
The bulb starts with a higher resistance. When
the filament starts to glow, it reduces the
resistance and the slope of the curve decreases.
It means that the bulb is faulty. A properly
functioning bulb should have a perfectly linear
graph, just like the resistors.
It means that the person increasing the voltage
stopped for a moment, then continued to turn
the knob.