Whenever the net force on an object is zero, its acceleration
A) may be less than zero.
B) is zero.
C) may be more than zero.
Diffuse reflection occurs when the size of surface irregularities is
A) small compared to the wavelength of the light used.
B) large compared to the wavelength of the light used.
C) microscopic.
Reactions that take place in a breeder reactor change
A) elements into different elements.
B) molecules into different molecules.
C) ions into different ions.
D) all of the above
E) none of the above
If the specific heat capacity of water were lower than it is, a watermelon in a picnic
cooler would cool in a
A) shorter time.
B) longer time.
C) the same time anyway.
One liter of water has a mass of
A) 1 kilogram.
B) 14.7 grams.
C) 500 grams.
D) none of the above
When a baseball player bats a ball with a force of 1000 N, the reaction force that the
ball exerts against the bat is
A) less than 1000 N.
B) more than 1000 N.
C) 1000 N.
D) need more information
A piece of putty moving with 1 unit of momentum strikes and sticks to a heavy bowling
ball that is initially at rest. Both move with a combined momentum of
A) less than 1 unit.
B) more than 1 unit.
C) 1 unit.
D) need more information
Each rolling wheel of a railroad train is tapered. Compared with the wide part, the
narrow part of the wheel has a tangential speed that is
A) less.
B) greater.
C) the same for both.
When a bimetallic bar made of copper and iron strips is heated, the bar bends toward
the iron strip. The reason for this is
A) iron gets hotter before copper.
B) copper gets hotter before iron.
C) copper expands more than iron.
D) iron expands more than copper.
E) none of the above
The strength of a rope depends on its
A) thickness.
B) length.
C) both of these
For a system in mechanical equilibrium, the resultant
A) force must be zero.
B) torque must be zero.
C) both of these
D) none of these
Although solid matter is mostly empty space, we don’t fall through the floor because
A) atoms are constantly vibrating, even at absolute zero.
B) of nuclear forces.
C) of gravitational forces.
D) of electrical forces.
E) none of the above
The force that accelerates the orange and apple system featured in your textbook is
actually supplied by the
A) apple.
B) orange.
C) floor.
Two charged particles held a certain distance apart are released. As they move, the
acceleration of each decreases. Therefore, their charges have
A) the same sign.
B) opposite signs.
C) need more information
For an isotope with a half-life of one day, at the end of two days the amount that
remains is
A) none.
B) one-half.
C) one-quarter.
D) one-eighth.
E) none of the above
When a blinking light source moves relative to you, the speed of the light
A) changes but the frequency of blinks remains constant.
B) remains constant but the frequency of blinks can change.
C) stays the same, as does the blinking frequency.
Compared to the energy it takes to separate oxygen and hydrogen from water, the
amount of energy released when they recombine is
A) slightly more.
B) slightly less.
C) much more.
D) much less.
E) the same.
Inside an accelerating spaceship in deep space, a sideways-tossed ball will
A) curve as it would in a gravitational field equal to the spaceship’s acceleration.
B) follow a straight-line path from one side of the interior to the other.
C) fall in a semi-circular path.
Parallax is evident when you view objects
A) with one eye.
B) with both eyes.
C) with one or both eyes.
D) in a completely dark room.
As a spaceship moving toward you at half the speed of light fires a probe toward you,
relative to itself at 0.7 the speed of light, you see the probe approaching at about
A) 0.70c.
B) 0.87c.
C) 0.89c.
D) 0.92c.
E) 0.96c.
Knowing that the atomic number of neon is greater than that of helium, at the same
temperature and pressure, how does the speed of sound in helium gas compare to the
speed of sound in neon gas?
A) greater in neon than in helium
B) greater in helium than in neon
C) the same in both gases
D) depends on the frequency of the sound generated
A photovoltaic cell receives energy input by
A) conduction.
B) convection.
C) radiation.
D) all of the above
According to the law of reflection, the incident light ray, the reflected light ray, and the
normal between them
A) lie in the same plane.
B) may or may not lie in the same plane.
C) lie in planes that are perpendicular to one another.
The fact that desert sand is very hot in the day and very cold at night is evidence that
the specific heat capacity of sand is relatively
A) low.
B) high.
C) practically absent.
The force exerted on an electron moving in a magnetic field is maximum when the
electron moves
A) parallel to the magnetic field.
B) perpendicular to the magnetic field.
C) either of these
D) neither of these
Which of these relate most to the loudness of sound?
A) wavelength.
B) frequency.
C) speed.
D) amplitude.
E) all of the above
A 5-kg fish swimming at 1 m/s swallows an absent-minded 1-kg fish at rest. The speed
of the larger fish after lunch is
A) 1/2 m/s.
B) 2/5 m/s.
C) 5/6 m/s.
D) 6/5 m/s.
E) 1 m/s.
A device that transforms mechanical energy into electrical energy is a
A) generator.
B) motor.
C) transformer.
D) magnet.
E) none of the above
Compared with the sum of isolated-nucleon masses, their collective mass in a
composite nucleus is
A) more.
B) less.
C) the same.
Einstein’s theory of gravitation
A) agrees with established results of Newton’s theory.
B) has been supported by repeated experiments.
C) incorporates Newton’s theory as a special case.
D) is superior to Newton’s where spacetime is more curved.
E) all of the above
Compared to the energy of a photon of red light, the energy of a photon of blue light is
A) less.
B) more.
C) the same.
Science, art, and religion normally need not contradict one another because
A) all three involve different domains.
B) choosing the right one means no need to heed the other two.
C) choosing religion and art means no need to heed science.
D) choosing science means no need to heed religion and art.
When you touch a hot potato with your finger, energy flows
A) from your finger to the potato.
B) from the potato to your finger.
C) actually, both ways.