Physics exam 2 (hw and pp)
Atoms are generally smaller than... A. molecules. B. microbes. C. the wavelength of visible light .D. All of these. E. None of these.
.D. All of these.
No force due to Earth's gravity is acting on the astronauts inside the orbiting space shuttle. This statement is: 1. always false. 2. always true while in orbit. 3. sometimes true while in orbit.
1. always false.
What is the mass density of water? What is water's normal weight density?
1000 kg/m3; 9800 N/m3
If a 1-L container is immersed halfway into water, what is the volume of water displaced? What is the buoyant force on the container? A. 0.5 L displaced, 5 N buoyant force B. 1 L displaced, 10 N buoyant force C. 0.5 L displaced, 10 N buoyant force D. 1 L displaced, 1 N buoyant force
A. 0.5 L displaced, 5 N buoyant force
What is the purpose of a model in science? A. A model is an abstraction that helps us visualize and predict. B. A model represents the world with equations. C. A model is a representation of an object as perfect as the original but on a different scale. D. A model is a scaled-up or scaled-down copy of an object. Submit
A. A model is an abstraction that helps us visualize and predict.
Why can atoms not be seen with a powerful optical microscope? A. Atoms are much smaller than a wavelength of light. B. Atoms are transparent and do not interact with light. C. Atoms are crystal clear and light passes right through them. D. All of the above
A. Atoms are much smaller than a wavelength of light.
How does the Moon "fall" without getting closer to us? A. It falls away from the straight path that it would follow if there were no forces acting on it. B. The Moon does not "fall." Instead, it moves in a circle at a constant radius. C. The Moon "falls" away from Earth a bit on every orbit. D. The Moon "falls" toward Earth a bit on every orbit.
A. It falls away from the straight path that it would follow if there were no forces acting on it.
What happens to the strength of the gravitational field at the surface of a star that shrinks? A. It increases. B. It stays the same. C. It first increases and then it decreases. D. It decreases.
A. It increases.
A loaded ship arrives at the first freshwater lock of the Panama Canal, will it float higher or lower than in the open ocean? A. It will float lower. B. It will float higher. C. I need to know the weight of the ship to answer. D. It will float at the same level.
A. It will float lower.
What great discovery followed finding perturbations in the planet Uranus? A. Neptune was discovered. B. Newton's law of universal gravitation was discovered. C. Einstein's theory of gravitation was discovered. D. Pluto was discovered.
A. Neptune was discovered.
Why were multiple vertical columns needed to support the roofs of stone buildings in ancient Egypt and Greece? A. Stone breaks under tension. B. Stone breaks under compression. C. Stone breaks along the neutral line. D.The columns are decorative elements.
A. Stone breaks under tension.
Which pulls on the oceans of Earth witha greater force? A. Sun B. Moon C. both pull the same.
A. Sun
Why do the astronauts in the Space Shuttle float around? A. The Space Shuttle is in free fall, so the shuttle and the astronauts inside it are continuously falling toward the Earth. They thus experience apparent weightlessness. B. There is no gravity in the Space Shuttle because it is too far away from the center of the Earth. C. There is no gravity in the Space Shuttle because it is completely enclosed and shielded from the effects of gravity due to the Earth.
A. The Space Shuttle is in free fall, so the shuttle and the astronauts inside it are continuously falling toward the Earth. They thus experience apparent weightlessness.
If you place a Styrofoam cup on the table and a bunch of BBs move around it randomly, what will happen to the cup, and why? A. The cup will move randomly in different directions because the BBs will exert unequal forces on the cup in different directions. B. The cup will move steadily in one direction because of the uniform force exerted by the BBs pushing it in that direction. C. The cup will not move, because it is much larger than the BBs. Submit
A. The cup will move randomly in different directions because the BBs will exert unequal forces on the cup in different directions.
There is a condition in which the buoyant force on an object does equal the weight of the object. What is this condition? A. The object is neutrally buoyant, so it will neither sink nor float. B. It will sink. C. It will float.I D. t will float almost completely out of the water.
A. The object is neutrally buoyant, so it will neither sink nor float.
Why is a metal spring said to be elastic? A. When deformed, it returns to its original shape. B. It does not obey Hooke's law. C. When deformed, it does not return to its original shape. D. It is made of steel
A. When deformed, it returns to its original shape.
What is the magnitude of the gravitational field at Earth's center? A. Zero N/kg B. g/2 N/kg C. 2g N/kg D.g N/kg Submit
A. Zero N/kg
If Earth's radius somehow increased with no change in mass, your weight would A. decrease. B. stay the same. C. increase also.
A. decrease.
Newton's most celebrated synthesis was and is of A. earthly and heavenly laws. B. weight on Earth and weightlessness in outer space. C. masses and distances. D. the paths of tossed rocks and the paths of satellites.
A. earthly and heavenly laws.
Einstein's theory of gravitation, compared with Newton's, _______. A. eliminates the role of force B. is one and the same C. enhances the role of force D. more greatly emphasizes the inverse-square law
A. eliminates the role of force
When you stand in an elevator accelerates upward, compared with your rest weight your weight reading on a scale is A. greater. B. less. C. zero. D. The same.
A. greater.
The smallest particle of a substance that consists of two or more atoms bonded together is called A. molecule B. atom C. substance D. matter
A. molecule
Do we see atoms directly or only indirectly with a scanning electron microscope? A. only indirectly B. only directly C. directly and indirectly D. A scanning electron microscope doesn't allow us to see atoms.
A. only indirectly
What makes an element distinct? A. the number of protons B. the number of neutrons C. the number of electrons D. the total mass of all the particles E. none of these
A. the number of protons
in our part of the universe, antimatter is: A.short-lived. B.long-lived. C.plentiful. D.none-existent E.fictional
A.short-lived.
What is the magnitude of Earth's gravitational force on a 1-kg body at Earth's surface? A. 6.67 × 10 -11 N1 B. 10 N C. 6.67 × 10 -11 kg D. 1 kg
B. 10 N
If a suspended 1-kg object stretches a spring by 4 cmcm, how much will the spring be stretched when it supports a 3-kg object? A. 9 cm B. 12 cm C. 5 cm D. 0.66 cm
B. 12 cm
What do you get if you rotate an arch through a complete circle? A. A semi-circle B. A dome C. A hyperbola D.A parabola
B. A dome
What is meant by the elastic limit for a common spring? A. A spring obeys Hooke's law only above its elastic limit. B. A spring is elastic up to the limit and inelastic above it. C. A spring is inelastic up to the limit and elastic above it. D. A spring breaks at its elastic limit.
B. A spring is elastic up to the limit and inelastic above it.
Why are all tides greatest at the time of a full Moon or new Moon? A.At full Moon and new Moon, the tides from the Moon and the Sun partially cancel because they make a right angle with Earth. B. At full Moon and new Moon, the tides from the Moon and the Sun add because they are in line with Earth. C. At full Moon and new Moon, the tides from the Moon and the Sun partially cancel because they are in line with Earth. D. At full Moon and new Moon, the tides from the Moon and the Sun add because they make a right angle with Earth.
B. At full Moon and new Moon, the tides from the Moon and the Sun add because they are in line with Earth.
What kind of attraction pulls electrons close to the atomic nucleus? A. Gravitational B. Electric C. Magnetic D. Nuclear
B. Electric
What type of force holds atoms together in a crystal? A. Magnetic B. Electric C. Gravitational D.Electromagnetic
B. Electric
How does one isotope differ from another? A. It has a different electric charge. B. It has a different number of neutrons. C. It has a different number of protons. D.It has a different number of electrons.
B. It has a different number of neutrons.
Who advanced the idea of atoms in the early 1800s? A. Robert Brown B. John Dalton C. Richard Feynman D. Albert Einstein
B. John Dalton
How did Einstein view the curved path of a planet? A. In an ellipse. B. Moving in curved 4-dimensional spacetime. C.In a straight line called a geodesic. D. ALWAYS AT REST
B. Moving in curved 4-dimensional spacetime.
Why does the gravity in the Space Shuttle compare with the gravity on Earth the way it does? a. The Space Shuttle is much farther away from the center of the Earth than the surface of the Earth. B. The Space Shuttle and the surface of the Earth are about the same distance from the center of the Earth. C. The Space Shuttle is much closer to the center of the Earth than the surface of the Earth.
B. The Space Shuttle and the surface of the Earth are about the same distance from the center of the Earth.
Why are heavier elements not much larger than lighter elements? A. Larger gravitational forces pull electrons into closer orbits. B. The larger positive charge in the nucleus pulls the electrons into closer orbits. C. Larger magnetic forces pull electrons into closer orbits. D.Larger nuclear forces pull the electrons into closer orbits.
B. The larger positive charge in the nucleus pulls the electrons into closer orbits.
Compared with the energy it takes to separate oxygen and hydrogen from water, how much energy is released when they recombine? (Think conservation of energy.) A. Less energy is released when they recombine. B. The same amount of energy is released when they recombine. C. More energy is released when they recombine. D.No energy is released when they recombine.
B. The same amount of energy is released when they recombine.
Why are occupants of the International Space Station weightless? A. Centripetal force cancels gravity in the space station. B. They are in free fall. C. They are so far from Earth that gravity is essentially zero. D. The floor of the space station is made from cavorite, which blocks gravity.
B. They are in free fall.
The number of atoms in a common water molecule is __________. A. One B. Three C. Four D.Two
B. Three
Do tides depend more on the strength of gravitational pull or on the difference in strengths? Explain A. Tides depend weakly on the difference and strongly on the strength. B. Tides depend only on the difference. C. Tides depend only on the strength. D. Tides depend on both the strength and the difference equally.
B. Tides depend only on the difference.
Why are the cross-sections of metal beams in the shape of the letter I instead of solid rectangles? A. To put the most material into the neutral layer B. To reduce the weight of the beam while preserving the resistance to bending C. To make the beam much stronger than a solid rectangular beam of the same width and height D. To give increased weight to a thin vertical beam
B. To reduce the weight of the beam while preserving the resistance to bending
The pressure increases on a block resting on a table when you increase the __________. A. downward force and surface area B. downward force on the block C. density of the block D. surface area
B. downward force on the block
Water pressure in a lake is ____________. A. greater at the surface B. greater at the bottom C. the same at any point D. greater midway to the bottom
B. greater at the bottom
The force of gravity acts on all apples on an apple tree.Some apples are twice as far from the ground as others. For the same mass these twice-as-high apples have A. 1/4 the weight. B. practically the same weight .C. 1/2 the weight.
B. practically the same weight
When an object moves away from the surface of Earth, the gravitational force decreases because A. its weight decreases B. the distance between Earth and the object increases C. its mass decreases D. its mass increases
B. the distance between Earth and the object increases
How many different elements are in a water molecule? A. one B. two C. three D. four E. none
B. two
The reason the Moon does not crash into the Earth is that the A) Earth's gravitational field is weak at the moon. B) gravitational pull of other planets keeps the moon up. C) Moon has a sufficient tangential speed. D) Moon has less mass than the Earth. E) none of these
C) Moon has a sufficient tangential speed.
According to Newton, doubling the distance between two interacting objects A) divides by 2 the gravitational force between them. B) multiplies by 2 the gravitational force between them. C) divides by 4 the gravitational force between them. D) multiplies by 4 the gravitational force between them.
C) divides by 4 the gravitational force between them.
If an object submerged in water displaces 10 kg of water, the buoyant force on the submerged object is __________. A. more than 100 N1 B. 0 N C. 100 N D. 10 kg
C. 100 N
How does close packing of iridium atoms affect the density of iridium? A. The density of iridium doesn`t depend on the close packing of its atoms. B. Close packing of iridium atoms accounts for its small density. C. Close packing of iridium atoms accounts for its great density.
C. Close packing of iridium atoms accounts for its great density.
Is it tension or compression that strengthens an arch that supports a load? A. Neither tension nor compression - it's the cement. B. Tension C. Compression D. Both tension and compression
C. Compression
Which of these atoms has the largest number of neutrons in the nucleus? A. Helium B. Hydrogen C. Gold D. Carbon
C. Gold
A scuba diver is planning to dive to the same depth in the open ocean and in a deep lake. Considering that salt water is denser that fresh water, where would the diver feel more pressure? A. In the lake B. We need to know the depth of the diver to answer this question. C. In the ocean D.Same in both
C. In the ocean
How does the electric charge of an electron compare with the electric charge of a proton? A. It is equal. B. It is about 2000 times larger and opposite in sign. C. It is equal and opposite. D. It is about 2000 times larger. Submit
C. It is equal and opposite.
How does the brightness of light change when the source is held twice as far away? A. It is ½ as bright. B. It is the same brightness. C. It is ¼ as bright. D. It is twice as bright. Submit
C. It is ¼ as bright.
What is Hooke's law? Does it apply to elastic materials or to inelastic materials? A. Stretch is inversely proportional to force for elastic materials. B. Stretch is proportional to force for elastic and inelastic materials. C. Stretch is proportional to force for elastic materials. D. Stretch is proportional to force for inelastic materials.
C. Stretch is proportional to force for elastic materials.
What happens to the force of attraction between two planets if their masses are doubled and the distance between them is also doubled? A. The force would quadruple. B. It would be half of the original force. C. The force would remain the same. D. The force would double.
C. The force would remain the same.
How does the gravity in the Space Shuttle compare with the gravity on Earth's surface? A. The gravity in the Space Shuttle is much smaller than the gravity on Earth's surface. B. The gravity in the Space Shuttle is much larger than the gravity on Earth's surface. C. The gravity in the Space Shuttle is approximately equal to the gravity on the surface of the Earth.
C. The gravity in the Space Shuttle is approximately equal to the gravity on the surface of the Earth.
How does water pressure 2 m below the surface of a small pond compare with water pressure 2 m below the surface of a huge lake? A. The pressure will be less. B. The pressure will be zero in both cases. C. The pressure will be the same. D. The pressure will be greater
C. The pressure will be the same.
With respect to volume, mass, and density, which changes when you squeeze a loaf of bread? What doesn't change? A. Volume increases, mass stays the same, density decreases. B. Volume increases, mass decreases, density stays the same. C. Volume decreases, mass stays the same, density increases. Volume stays the same, mass increases, density decreases.
C. Volume decreases, mass stays the same, density increases.
Why is a blob of bread dough said to be inelastic? A. It obeys Hooke's law. B. It doesn't make of rubber. C. When deformed, it does not return to its original shape. D. When deformed, it returns to its original shape.
C. When deformed, it does not return to its original shape.
If you weigh yourself in an elevator, the scale will indicate the greatest weight when the elevator A. moves upward at constant speed. B. moves downward at constant speed. C. accelerates upward. D. accelerates downward.
C. accelerates upward.
Surrounding a magnet is a magnetic field. Surrounding an electron is an electric field. Surrounding Earth is A. an alteration in space in which mass experiences a force. B. a gravitational field. C. both of these D. neither of these
C. both of these
Of the four fundamental forces presently known, the force of gravity is A. the same as the others B. the strongest C. the weakest D. always downward
C. the weakest
When is your weight measured as mg? A.For a mass accelerating downward with an acceleration g B. For a mass accelerating upward with an acceleration g near the surface of Earth C.For a non-accelerating mass near the surface of Earth D. For a mass near the surface of Earth in free fall
C.For a non-accelerating mass near the surface of Earth
The name given to the shape of a sagging rope supported at its ends is a ____________. A. hyperbola B. parabola C.catenary D.semi-circle
C.catenary
Who first explained Brownian motion and made a convincing case for the existence of atoms? A. John Dalton B. Richard Feynman C. Robert Brown D. Albert Einstein
D. Albert Einstein
What did Newton discover about gravity that was not known at the time? A. The Newtonian synthesis B.The equation for the force of gravity C. The law of universal gravitation D. All of the above
D. All of the above
Which of the following are incorrect statements about the atoms? A. Atoms are smaller than the wavelength of visible light. B. Most of an atom's volume is empty space, just as the solar system is mostly empty space. C. Atoms are perpetually moving. D. Atoms are manufactured in plants, and in humans during pregnancy. E. All are correct.
D. Atoms are manufactured in plants, and in humans during pregnancy.
In terms of atom arrangements, distinguish between crystalline and noncrystalline substances. A. Atoms in crystals are located in a cubic array. In amorphous materials, they are hexagonal. B. Atoms in amorphous materials are in an ordered array. In crystals, they are randomly distributed. C. Atoms in crystals are closer together than atoms in amorphous materials. D. Atoms in crystals are in an ordered array. In amorphous materials, they are randomly distributed.
D. Atoms in crystals are in an ordered array. In amorphous materials, they are randomly distributed.
Why is there no horizontal buoyant force on a submerged object? A. Forces on the sides are zero at every point. B. Forces on the top and bottom add and cancel gravity. C. Force vectors on the top and bottom cancel one another. D. Force vectors on the sides cancel one another
D. Force vectors on the sides cancel one another
If you punch holes in the side of a container filled with water, in what direction does the water initially flow outward from the container? A. The bottom one comes straight out, whereas the upper ones come out at a downward angle. B. It comes out 45 degrees below horizontal. C. It drops straight down. D. It flows straight out, perpendicular to the wall
D. It flows straight out, perpendicular to the wall
What is a gravitational field, and how can its strength be measured? A. It is a force field in empty space with direction and magnitude equal to the inverse square of the mass of a test mass. B. It is a force field on a body with mass, with direction and magnitude equal to the inverse square of the distance to a test mass. C. It is a force field with direction and magnitude at every point in space. It's strength is the force on a test mass. D. It is a force field on any body with mass. Its strength is the force per unit mass on a test mass
D. It is a force field on any body with mass. Its strength is the force per unit mass on a test mass
Are most of the atoms around us younger or older than the Sun? A. Most are younger than the Sun B. Most are much younger than the Sun C. Most are the same age as the Sun D. Most are older than the Sun
D. Most are older than the Sun
Both the Moon and the Sun produce our ocean tides, but the tides are primarily due to the Moon. Why? A. The lunar pull is stronger. B. The Sun is farther away. C. The moon is closer. D. The difference in lunar pulls is greater than the difference in solar pulls
D. The difference in lunar pulls is greater than the difference in solar pulls
Part complete How does the force of gravity between two bodies change when the distance between them is halved? A.The force decreases to ¼ of its initial value. B. The force doubles. C. The force is cut in half. D. The force quadruples. Submit
D. The force quadruples. Submit
Why does the buoyant force act upward on an object submerged in water? A. Water shields the object from gravity. B. The pressure downward on the deeper bottom is less than the upward pressure on the top. C. The pressure upward on the top is greater than the downward pressure on the deeper bottom. D. The pressure upward on the deeper bottom is greater than the downward pressure on the top.
D. The pressure upward on the deeper bottom is greater than the downward pressure on the top.
Why it is not possible to directly observe or photograph a black hole? A. They are very massive. B. They are very small. C. They are blocked by other objects. D. Their gravity is so strong that nothing, not even light, can escape a black hole.
D. Their gravity is so strong that nothing, not even light, can escape a black hole.
What occurs when a proton and an antiproton meet? A.They electrically repel each other. B. They do not interact in any way. C. They gravitationally repel each other. D. They annihilate each other.
D. They annihilate each other.
Where do you weigh more--at the bottom of Death Valley or atop one of the peaks of the Sierra Nevada? Defend your answer. A. You weigh more on the summit because the air buoys you up less. B. You weigh more in Death Valley because more atmosphere pushes down on you. C. You weigh more on the summit, because the higher you go, the harder you fall. D. You weigh more in Death Valley because you are closer to the center of Earth.
D. You weigh more in Death Valley because you are closer to the center of Earth.
How could your weight be greater than mg? How could your weight be zero? Give examples. A. Your weight is greater than mg when you are on top of a mountain. Your weight is zero when you are in free fall. B. Your weight is greater than mg when you are in free fall. Your weight is zero when you are accelerating upward. C. Your weight is greater than mg when you are accelerating downward. Your weight is zero when you are in free fall. D. Your weight is greater than mg when you are accelerating upward. Your weight is zero when you are in free fall.
D. Your weight is greater than mg when you are accelerating upward. Your weight is zero when you are in free fall. Submit
An atomic mass unit (amu) is 1/12 the mass of A. an electron. B. a proton. C. a hydrogen atom. D. a carbon atom. E. an uranium atom.
D. a carbon atom.
The mass of an atom is __________. A. mostly electrons B. very, very small C. impossible to calculate D. concentrated in the atomic nucleus
D. concentrated in the atomic nucleus
When you use an I-beam in a horizonal application, the region between the flanges is ____________. A. compressed B. squeezed C. stressed D. free of stress
D. free of stress
Dark matter is considered to be __________. A. a form of dark energy B. a local phenomenon C. at the center of all atomic nuclei D. plentiful in the universe
D. plentiful in the universe
A stone of volume V submerged in water displaces the _________. A. same density times volume B. same weight of water C. same volume and weight of water D. same volume of water
D. same volume of water
Atoms heavier than helium were made by A. radiant energy conversion .B. photosynthesis. C. radioactivity. D. thermonuclear fusion. E. none of these
D. thermonuclear fusion.
Atoms in a crystalline state or in an amorphous state are A. flowing B. in fixed positions C. in random positions D. vibrating about their own positions
D. vibrating about their own positions
What is the most abundant element in the known universe? A. Carbon B. Iron C. Helium D.Hydrogen
D.Hydrogen
State Newton's law of universal gravitation in words. A. The force is proportional to the product of two masses and to the square of the distance between their centers. B. The force is proportional to the product of two masses. C. The force is proportional to the product of two masses and inversely proportional to the distance between their centers. D.The force is proportional to the product of two masses and inversely proportional to the square of the distance between their centers.
D.The force is proportional to the product of two masses and inversely proportional to the square of the distance between their centers.
Rank the following scientific discoveries from first to last: Rank from first to last. Discovery of the atom Discovery of the electron Discovery of Brownian motion
Discovery of Brownian motion Discovery of the atom Discovery of the electron
Consider two planets in space that gravitationally attract eachother. If the masses of both planets are doubled, and the distance between them is also doubled, then the force between them is A) one quarter .B) half as much. C) twice as much. D) four times as much. E) none of these
E) none of these
If you swim beneath the surface in saltwater, will the pressure be greater than in freshwater at the same depth? Why or why not? A. The pressure will be less because saltwater is less dense. B. The pressure will be greater because saltwater is less dense. C. The pressure will be less because saltwater is more dense. D. The pressure will be the same because it only depends on the depth. E. The pressure will be greater because saltwater is more dense.
E. The pressure will be greater because saltwater is more dense.
If 1.0 Gram of Antimatter Meets With 4.0 Grams of Matter, the Energy Released Would Correspond to the Energy Equivalent of a) 1 gram. b) 2 grams. c) 4 grams. d) much more than 4 grams.
b) 2 grams.
The Reason You Don't Fall Between the Atoms in the Floor You Stand on Involves a) the small spaces between atoms. b) electrical forces. c) the rigidity of solids. d) pressure.
b) electrical forces.
When a tree branch is bent, the region in the center of the branch is the __________. a. elastic layer b.neutral layer c. tensile layer d. compressed layer
b.neutral layer
Unique experiments can be carried out in theSpace Station because of the lack of gravity. a) Yes, and the Space Station was built in order to escape gravity b) This is not quite right—the Space Station still feels the effect ofEarth's gravity but it is greatly diminished and the experiments are therefore referred to as being performed in "micro-gravity" c) No, the uniqueness of the experiments is not due to the lack of gravity but due to weightlessness d) No, similar experiments can be performed on the surface of Earth e) No, similar experiments can be performed on the highest mountaintops on Earth
c) No, the uniqueness of the experiments is not due to the lack of gravity but due to weightlessness
Each of us weighs a tiny bit less inside the ground floor of a skyscraper than we do on the ground away from the skyscraper. The reason for this is the A) gravitational field is shielded inside the building and massof the building attracts us upward slightly. B) gravitational field is shielded inside the building. C) mass of the building attracts us upward slightly. D) none of the given variants.
c. mass of the building attracts us upward slightly.
The Atoms That Make Up Your Body a) were formed in stars. b) are older than the Earth. c) are in motion at all times. d) All of these.
d) All of these.
