An electric heater is rated 300W 110V. The safety fuse in the circuit can withstand 15 A
of current. How many heaters can be safely operated in the circuit?
A) 2
B) 3
C) 4
D) 5
E) more than 5
Answer:
A clerk can lift cylindrical packages 1 meter vertically, or can roll them up a
2-meter-long ramp to the same elevation. With the ramp, the applied force required is
about
A) half as much.
B) the same.
C) twice as much.
D) four times as much.
Answer:
A razor blade nicely shows diffraction fringes when illuminated with
A) ultraviolet light.
B) monochromatic light.
C) sunlight.
D) all of the above
E) none of the above
Answer:
When we say an appliance “uses up electricity,” we mean
A) current disappears.
B) electric charges are dissipated.
C) voltage is lowered.
D) electric energy dissipates into heat.
Answer:
The fate of the world’s uranium supply is to eventually become
A) alpha and beta particles.
B) iron.
C) lead.
Answer:
If you walk towards a mirror at a certain speed, the relative speed between you and your
image is
A) half your speed.
B) your speed.
C) twice your speed.
D) none of the above
Answer:
Light from two closely-spaced stars cannot produce a steady interference pattern due to
A) incoherence.
B) the inherent instability of the atmosphere.
C) their different radial distances.
D) their non-point like natures.
E) closely spaced stars not producing interference patterns.
Answer:
A lamp rated 23W 120V means that it will deliver 23 W
A) when the voltage across it is 120 V.
B) whether or not it is connected to 120 V.
C) as long as the current is ac.
D) none of the above
Answer:
When you adjust a telescope to get a clear image of Saturn’s rings, there is a perceptible
interaction between
A) you and the telescope.
B) you and Saturn’s rings.
C) both of these
D) neither these
Answer:
For radio reception in city buildings, diffraction is
A) helpful.
B) a hindrance.
C) not a factor.
Answer:
Radiation dosage is commonly measured in
A) rads.
B) rems.
C) joules.
D) none of the above
Answer:
A cannonball following a parabolic path explodes into fragments. The momentum of
the fragments
A) continue along the path as if the explosion didn’t occur.
B) cancels to zero by vector addition.
C) both of these
D) neither of these
Answer:
The wavelength of a particle relates to its
A) momentum.
B) energy levels.
C) quantum number.
D) all of the above
E) none of the above
Answer:
According to general relativity, a photon emitted by a star
A) loses energy.
B) reduces in frequency.
C) is red-shifted.
D) all of the above
E) none of the above
Answer:
The metal in a chunk of copper or iron is composed of
A) crystals.
B) non-crystalline fibers.
C) amorphous particles.
D) none of the above
Answer:
Solar power is used in many parts of the world for
A) heating water.
B) generating electricity.
C) both of these
D) neither of these
Answer:
A lunar month is about 28 days. If the Moon were farther from Earth than it is now, the
lunar month would be
A) less than 28 days.
B) about 28 days.
C) more than 28 days.
D) need more information
Answer:
If you quickly run toward the orchestra at a concert, the frequency of the sound you
hear will be
A) decreased.
B) increased.
C) neither of these
Answer:
The balance between electrical and nuclear strong forces is more tenuous in
A) light elements.
B) middle size elements like iron.
C) heavier elements.
D) all of the above
E) none of the above
Answer:
A rocket coasts in an elliptical orbit about Earth. To attain escape velocity using the
least amount of fuel in a brief firing time, should it fire off at the apogee, or at the
perigee? (Hint: Let Fd = ∆ KE guide your thinking.)
A) perigee, where it is closest and fastest
B) apogee, where it is farthest and slowest
C) same at either location
D) same at any location
Answer:
Two photons that have the same wavelength also have the same
A) frequency.
B) energy.
C) both of these
D) neither of these
Answer:
The radiation curve for a blue hot star peaks in the
A) infrared region.
B) red region.
C) yellow region.
D) ultraviolet region.
E) none of the above
Answer:
The fanning out of waves upon passing through an opening is more pronounced through
A) small openings.
B) large openings.
C) same for each
D) none of the above
Answer:
As the speed of a particle approaches the speed of light, the momentum of the particle
A) approaches zero.
B) approaches infinity.
C) transforms to energy.
D) is no longer in spacetime.
Answer:
Relative to some reference frame in the universe, you may now be traveling at a speed
A) faster than the speed of light.
B) slower than the speed of light.
C) at the speed of light.
D) any of the above
Answer:
The bob of a conical pendulum swings in a
A) to-and-fro path.
B) circular path.
C) chaotic path.
Answer:
An astronaut traveling forward at 0.87c holds a meterstick in spear-like fashion. This
astronaut sees the spear’s length as
A) 0.5 m.
B) 0.87 m.
C) 1 m.
D) 1.25 m.
E) 1.5 m.
Answer:
A liter of cold water will warm faster in sunlight in a
A) black pot.
B) silver pot.
C) red pot.
D) none of the above
Answer:
Which unit represents the most energy?
A) calorie
B) Calorie
C) joule
D) all the same
Answer:
What horizontally-applied force will accelerate a 400-kg crate at 1 m/s2 across a factory
floor against a friction force half its weight?
A) 600 N
B) 1600 N
C) 2000 N
D) 2400 N
E) none of the above
Answer:
While Earth is experiencing a total solar eclipse, an observer on the side of the Moon
facing Earth would see
A) Earth disappear from the sky.
B) Earth dim and turn reddish.
C) nothing unusual.
D) a dark area moving across the face of Earth.
Answer:
Electrons fired in vintage TV tubes traveled at about 0.25 times the speed of light,
having more momentum and energy than would be required classically to get that
speed. Strictly speaking, this
A) increased your electric bill.
B) decreased your electric bill.
C) had no effect on your electric bill.
Answer: