Physics Test #3 (ch9,11,12,13)
Consider the fictional case of the incredible shrinking man. If he shrinks proportionately to 1/10 his original height, his weight will be multiplied by
0.001
Consider the fictional case of the incredible shrinking woman. If her height shrinks to 0.1 times her original height, then her total skin area shrinks to
0.01 times its original value
A metal block has a density of 5000 kg per cubic meter and a volume of 2 cubic meters. What is the block's mass?
10,000 kg
How many individual atoms are in a water molecule?
3
The number of atoms in a common water molecule is
3
A metal block has a density of 5000 kg per cubic meter and a mass of 15,000 kg. What is its volume?
3 cubic meters
Doubling the thickness (diameter) of a rope will multiply its strength by
4
When a living cell doubles in diameter, the amount of its material to be nourished is multiplied by eight, but the amount of membrane through which to feed it is multiplied by
4
A wooden block has a mass of 1000 kg and a volume of 2 cubic meters. What is the block's density?
500 kg per cubic meter
Which of the following has the greatest outer surface area?
an elephant
You take 1000 mg of a vitamin and your friend takes 1g of the same vitamin. Who takes more vitamins?
both the same
If a loaf of bread is compressed, its
density increases
Which of these atoms has the largest number of neutrons in there nucleus? helium, hydrogen, carbon or gold
gold
Compared to the volume of a kilogram of feathers, the volume of a kilogram of lead is
less
The charge in the nucleus of an antimatter hydrogen atom is
negative
If two protons are ADDED to an oxygen nucleus, the result is
neon
When a tree branch is bent, the region in the center of the branch is the
neutral layer
What is electrically neutral?
neutron
If we doubled the magnifying power of the most powerful optical microscope in the world we would still
not be able to see or photograph an atom
If you make cupcakes and bake them as directed for a cake, you will find the cupcakes
overbaked
In our part of the universe, antimatter is
short-lived
Assuming all the atoms exhaled by Julius Caesar in his last dying breath are still in the atmosphere, then we probably breathe one of those atoms with each
single breath
What did Robert Brown see under the microscope?
specks of dust moving around
Which geometrical shape has the least surface area for a given volume?
sphere
An electrical force determines
the chemical properties of an atom
If you place a styrofoam cup on the table & a bunch of BBs move around it randomly, what will happen to the cup & why?
the cup will move randomly in different directions b/c the BBs will exert unequal forces on the cup in different directions
What makes an element distinct?
the number of protons
Why did the particles Robert Brown saw under the microscope move around?
the particles were struck by atoms but unequally on different sides
Compared to a bar of pure gold, the density of a pure gold ring is
the same
There are about as many atoms of air in our lungs at any moment as there are breaths of air in the atmosphere of
the whole world
Atoms heavier than helium were made by
thermonuclear fusion
Which of the following is not an element: hydrogen, carbon, oxygen, water?
water
Half way to the center of a completely hollow planet with a thin uniform shell, your weight would be
0
If an object suspended by a scale shows a weight of 3N in air, and 2 N when submerged in water, the buoyant force on the submerged object is
1 N
Buoyant force is greatest on a submerged
1 kg block of aluminum
One liter of water has a mass of
1 kilogram
What is the buoyant force acting on a 10-ton ship floating in the ocean?
10 tons
A weight watcher who normally weighs 400 N stands on top of a very tall ladder so she is one Earth radius above the Earth's surface. How much would she weigh there?
100 N
Compared to the mass of a hydrogen atom, the mass of an oxygen atom is
16 times as great
What is the molecular mass of a water molecule?
18 amu
How many different elements are in a water molecule?
2
How many protons should be added to the nuclei of oxygen atoms so the resulting gas will glow red when there is an electrical current through it?
2
A weightless spring is stretched 10 cm by a suspended 1-kg block. If two such springs are used to suspend the block, one spring above the other, to effectively provide one double-length spring, then the total stretch of the double-length spring will be
20 cm
An asteroid exerts a 360-N gravitational force on a nearby spacecraft. If the spacecraft moves to a position three times as far from the center of the asteroid, the force will be
40 N
A spring is stretched 10 cm by a suspended 1-kg block. If two such springs side-by-side are used to suspend the block, so each spring supports half the weight of the block, then each spring will stretch
5 cm
What is the force of gravity on a 500-newton woman standing on the Earth's surface?
500 N
An unstretched hanging spring is 50 cm long. Suspending a 100-N weight from it makes its length 60 cm. Adding another 100-N weight will make the spring's length
70 cm
How many atoms are in a molecule of ethanol?
9
How much force is needed to hold a nearly weightless but rigid 1-L carton beneath the surface of water?
9.8 N
What is the weight of a cubic meter of ice?
9200 N
If you want to light some wood on fire, what would most likely make the wood light, and why?
Breaking the log down into small pieces of wood will increase the amount of wood surface that can catch fire
If two protons and two neutrons are removed from the nucleus of an oxygen atom, what nucleus remains?
C-12
If you want to cool down a drink with ice, which of the following would make it cool faster and why?
Crushing the lump into small pieces will put more of the ice's surface area is in contact with the drink
What element results if you add a pair of protons to the nucleus of mercury?
Pb
What is the buoyant force that acts on a submerged object equal to?
The buoyant force is equal to the weight of the fluid displaced by the submerged object
Suppose you increase the depth of the object WITHOUT changing its height. What will happen to the force due to pressure on the bottom of the object?
The force due to pressure on the bottom of the object will increase
Suppose you increase the height of the object WITHOUT changing its depth under water. What will happen to the force due to pressure on the bottom of the object?
The force due to pressure on the bottom of the object will increase
Which of the following items would remain without rusting longer: a solid lump of steel, or steel wool that weighs the same amount?
The lump of steel would stay without rusting longer, because not as much of it comes in contact with the air
Why do French fries cook faster when they are cut into thinner pieces, and why do meatballs cook faster when they are flattened?
There is a greater amount of surface area for the same amount of food in the thinner fries and flattened meatballs
Which of the following has the greatest outer surface area per volume?
a grape
Which has more volume, a kilogram of gold or a kilogram of aluminum?
a kilogram of aluminum
Which has more mass, a liter of ice or a liter of water?
a liter of water
Atoms are incredibly tiny, numerous, perpetually moving &
ageless
The amount of gravitational force that acts on the space shuttle while in orbit is
almost as much as the shuttle's weight on the Earth's surface
Nuclei that make up a newborn baby were made in
ancient stars
A strong spring is stretched 10 cm by a suspended weight. If the weight is doubled, the spring will stretch
another 10 cm which will make the total stretch 20 cm
Which of the following is stronger per body weight?
ant
Inside a freely falling runaway elevator, your
apparent weight is 0
water pressure in a lake is greater
at the bottom
Which has the greater density, a lake full of water or a cup full of lake water?
both have the same density
The Earths gravitational field extends
both inside and outside the Earth and throughout the entire universe
Water pressure is greatest against the
bottom of a submerged object
When an object is partly or wholly immersed in a liquid, it is buoyed up
by a force equal to the weight of liquid displaced
If two protons are REMOVED from an oxygen nucleus the result is
carbon
An atomic mass unit (amu) is 1/12 the mass of a
carbon atom
The name given to the shape of a sagging rope supported at its ends is a
catenary
surface tension is a direct result of
cohesive forces between molecules in a liquid
Black holes are essentially
collapsed stars
When weight is applied to the top of a stone arch, all of the stone blocks in the arch undergo
compression
stone slabs are stronger under
compression
If the Earth's mass decreased to one-half its original mass with no change in radius, then your weight would
decrease to one half your original weight
The pressure in a liquid depends on liquid
depth & density
According to Newton, doubling the distance between two interacting objects
divides by 4 the gravitational force between them
If the mass of an object were to double while its volume remains the same, its density would
double
An object is placed exactly halfway between the Earth and moon. The object will fall toward the
earth
Solid matter is mostly empty space. The reasons solids don't fall through one another is b/c of
electrical forces
The chemical properties of matter come mostly from its
electrons
The volume of matter comes mostly from its
electrons
What is negatively charged?
electrons
Hydrogen is considered an
element b/c it is composed of only one kind of atom
Which has more skin, an elephant or a mouse?
elephant
Einstein's theory of gravitation, compared with Newton's
eliminates the role of force
The buoyant force on a floating object is
equal to the objects weight
When you float in fresh water, the buoyant force that acts on you is equal to your weight. When you float higher in the high-density water of the Dead Sea, the buoyant force that acts on you is
equal to your weight
Blood pressure is normally greater in your
feet
How far must one travel to get away from the Earth's gravitational field?
forget it, you can't travel far enough
To become a negative ion, does an atom lose or gain an electron?
gains
When carbon & oxygen atoms combine, energy is
given off by the reaction
Consider the following atoms: Gold, Copper, Carbon & Silver - rank them greatest to least
gold, silver, copper, carbon
A kilogram of peaches have more skin area than a kilogram of
grapefruits
Lobsters live at the bottom of the ocean. The density of a lobster is
greater than the density of sea water
If the volume of an object were to double while its mass stays the same, its density would
halve
If one neutron is added to a helium nucleus, the result is
helium
When a boat sails from fresh water to salt water, the boat will float
higher in the water
If the mass of the Earth somehow increased with no change in radius, your weight would
increase also
Two objects move toward each other because of gravity. As the objects get closer and closer, the force between them
increases
An iron block is placed in a furnace where it is heated and consequently expands. In the expanded condition, its density
is less
The volume of water displaced by a floating 20-ton boat
is the volume of 20 tons of water
Suppose all sized potatoes are selling at the same price per kilogram. If you peel them for mashing, you will get more potato for your money if you buy
large potatoes
A block of aluminum with a mass of 1 kg is placed in a beaker of water filled to the brim. Water overflows. The same is done in another beaker with a 1-kg block of lead. Does the lead displace more, less, or the same amount of water?
less
A block of aluminum with a weight of 10 N is placed in a beaker of water filled to the brim. Water overflows. The same is done in another beaker with a 10-N block of lead. Does the lead displace more, less, or the same amount of water?
less
A lobster crawls onto a bathroom scale submerged at the bottom of the ocean. Compared to its weight above the surface, the lobster will have an apparent weight under water that is
less
Eight little spheres of mercury coalesce to form a single sphere. Compared to the combined surface areas of the eight little spheres, the surface area of the big sphere is
less
A candymaker making taffy apples decides to use 100 kg of large apples rather than 100 kg of small apples. Will the candymaker need to make more or less taffy to cover the apples?
less taffy
A liter-sized block of ordinary wood floats in water. The amount of water displaced is
less than 1 liter
Pumice is a volcanic rock that floats. Its density is
less than the density of water
To become a positive ion, does an atom lose or gain an electron?
loses
Compared to an empty ship, the same ship loaded with Styrofoam will float
lower in the water
In cold weather, your hands will be warmer if you wear
mittens over gloves
Surface tension is caused by
molecular attractions
Compared to the density of a kilogram of feathers, the density of a kilogram of lead is
more
A candymaker is making taffy apples. If she buys 100 kg of small apples rather than 100 kg of large apples, she will need
more taffy
The reason a granite block is mostly empty space is that the atoms in the granite are
mostly empty space themselves
Which has more skin compared to its body weight, an elephant or a mouse?
mouse
electron
negatively charged particle that whizzes about within an atom
An object having the same density of water will
neither sink nor float in water
The pascal is a pressure unit equal to one
newton per square meter
If no molecules in a body could escape, would the body have an odor?
no
A hollow spherical planet is inhabited by people who live inside it, where the gravitational field is zero. When a very massive space ship lands on the planet's surface, inhabitants find that the gravitational field inside the planet is
non zero, directed toward the spaceship
If each dimension of a steel bridge is scaled up ten times, its strength will be multiplied by about
one hundred, but its weight by one thousand
In an electrically neutral atom, the number of protons in the nucleus is balanced by an equal number of
orbital electrons
The buoyant force on an object is least when the object is
partly submerged
Dark matter is considered to be
plentiful in the universe
The force of gravity acts on all apples on an apple tree. Some apples are twice as far from the ground as others. These twice-as-high apples, for the same mass, have
practically the same weight
The weight of matter comes mostly from its
protons & neutrons
Which is the smallest particle - a molecule, a neutron, a proton, a atom or a quark?
quark
Brownian motion has to do with the
random motions of atoms & molecules
When a star collapses to form a black hole, its mass
remains the same
Two life preservers have identical volumes, but one is filled with Styrofoam while the other is filled with sand. When the two life preservers are fully submerged, the buoyant force is greater on the one filled with
same on each as long as their volumes are the same
Two life preservers have identical volumes, but one is filled with Styrofoam while the other is filled with sand. When the two life preservers are worn by swimmers so that one swimmer floats with part of the preserver above water, and the other swimmer sinks, the buoyant force is actually greater on the life preserver filled with
sand
a black hole is
simply the remains of a giant star that has undergone gravitational collapse.
Which of these is most elastic? steel, putty, water or air
steel
Molecules are the smallest subdivision of matter that
still retains chemical properties of a substance
The pressure at the bottom of a jug filled with water does NOT depend on
surface area of the water
The factor most directly responsible for making a black hole invisible is its
surface escape velocity
When a load is placed on the middle of a horizontal beam supported at each end, the bottom part of the beam undergoes
tension
Newton discovered
that gravity is universal
When holes are drilled through the wall of a water tower , water will spurt out the greatest horizontal distance from the hole closest to
the bottom of the tower
The reason a life jacket helps you float
the density of both you and the jacket together is less than your density alone.
An egg is placed at the bottom of a bowl filled with water. Salt is slowly added to the water until the egg rises and floats. From this experiment, one concludes
the density of salt water exceeds the density of egg
On what factors does the buoyant force acting on an object depend?
the height of the object
Suppose you increase the height of the object WITHOUT changing its depth under water. What will happen to the net buoyant force?
the net buoyant force will increase
Suppose you increase the depth of the object WITHOUT changing its height. What will happen to the net buoyant force?
the net buoyant force will stay the same
Compared to the atoms that make up the body of an elderly person, the atoms that make up the body of a newborn baby are
the same age
A block of aluminum with a volume of 10 cm3 is placed in a beaker of water filled to the brim. Water overflows. The same is done in another beaker with a 10-cm3 block of lead. Does the lead displace more, less, or the same amount of water?
the same amount
The caissons of the Falkirk Wheel are balanced only when
their water levels are the same
the strength of a rope depends on its
thickness
An asteroid exerts a 360-N gravitational force on a nearby spacecraft. This force is directed
toward the asteroid
According to Hooke's law, if you double the force when stretching a spring, the elongation of the spring is normally
twice as much
When a chocolate bar is cut in half, its density is
unchanged
The reason that buoyant force acts upward on a submerged object is that
upward pressure against the bottom is greater than downward pressure against the top of the submerged object
Which of these has the most atomic mass? hydrogen, lead, iron, uranium or they all have the same amount
uranium
A fish normally displaces its own
volume & weight of water
A completely submerged object always displaces its own
volume of fluid
A stone submerged in water displaces its
volume of water
The density of a submerged submarine is about the same as the density of
water
A dam is thicker at the bottom than at the top partly because
water pressure is greater with increasing depth
An important feature of atoms is that they have
wave properties
