Section 2

Question 1

______ are the smallest subdivision of matter that retains the chemical properties of a substance.

Answer 1

Atoms

Question 2

Which of the following is not a mixture: a) granite; b) cake; c) air; d) beach sand; e) All of the above are mixtures.

Answer 2

e) All of the above are mixtures.

Question 3

A force that determines the chemical properties of an atom is a(n)

Answer 3

electrical force.

Question 4

Muller’s micrograph reveals: a) a peek at actual atoms; b) the position of atoms; c) x-ray patterns; d) All of the above.

Answer 4

b) the position of atoms.

Question 5

An x-ray diffraction pattern of a solid indicates that the solid is

Answer 5

crystal.

Question 6

A cup of water and a big tank of water, which one has higher density?

Answer 6

Both are the same.

Question 7

The mass of a cubic meter of water is

Answer 7

1000 kg.

Question 8

One liter of water has a mass of

Answer 8

1 kilogram.

Question 9

A 10 cm long spring extends to 12 cm when a 1 kg load is suspended from it. What would be its length if a 3 kg load were suspended from it?

Answer 9

16 cm.

10 cm + 2 cm for 1 kg; add 2 kg more means
2 cm + 2 cm + 2 cm = 6 cm + original 10 cm = 16 cm

Question 10

The shape that has the greatest strength in construction is the

Answer 10

triangle.

Question 11

When you sit in the middle of a horizontal bench supported at its ends, the top side of the bench is

Answer 11

compressed and the bottom is stretched.

Question 12

If Alice in Wonderland shrinks to one-tenth her size, the ratio of her surface area/volume will

Answer 12

increase.

Question 13

Suppose you scale up a model machine by a factor of 4. Then its value is

Answer 13

64 times as much and its surface area is 16 times as much.

volume means ^3 so, 4^3 = 64
surface means ^2 so, 4^2 = 16

Question 14

When you stand on one foot instead of two, the force you exert on the floor is

Answer 14

the same.

The force you exert on the floor is your weight, which stays the same.

Question 15

When you stand on one foot instead of two, the pressure you exert on the floor is

Answer 15

more.

The pressure is force/area. The area of one foot is less than both feet, which means more pressure.

Question 16

Pressure in air or water is: a) mass per area; b) weight per area; c) volume per area; d) density per area; e) energy per area.

Answer 16

b) weight per area.

Question 17

Swim twice as deep, then the water pressure on you is

Answer 17

twice as much.

Question 18

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

Answer 18

bottom of the tower.

Question 19

Water pressure provided by a water tower is greater if the tower

Answer 19

is taller.

Question 20

A dam is thicker at the bottom than at the top partly because

Answer 20

water pressure is greater with increasing depth.

Question 21

Pumice is a volcanic rock that floats. Its density is: a) less than the density of water; b) equal to the density of water; c) more than the density of water.

Answer 21

a) less than the density of water.

Question 22

What is the buoyant force acting on a 10 ton ship floating in the ocean?

Answer 22

10 tons.

Question 23

A ship passed through a canal, and run from freshwater to saltwater, it will

Answer 23

float higher in saltwater and experience the same buoyant force.

Question 24

Which would float highest in the water: a) Loading a boat with 30 tons of lead evenly spread across the surface; b) Loading a boat with 30 tons of lead concentrated in a small hold; c) Loading a boat with 40 tons of boxes filled with air stacked high; d) Loading a boat with 15 tons of lead boxes stacked high.

Answer 24

d) Loading a boat with 15 tons of lead boxes stacked high.

Question 25

Ice floats because

Answer 25

ice is less dense than water.

Question 26

When a given mass of water freezes, it undergoes a

Answer 26

increase in volume.

Question 27

A completely submerged object always displaces its own

Answer 27

volume of fluid.

Question 28

The reason a life jacket helps you float is

Answer 28

the density of both you and the jacket together is less than your density alone.

Question 29

A 50 g wood block and a 50 g iron block submerged in water, which of them experiences a greater buoyant force?

Answer 29

Wood block.

Question 30

The difference in the upward and downward forces acting on the submerged block is: a) getting bigger at deeper place; b) getting smaller at deeper place; c) the same at any depth; d) none of the above.

Answer 30

c) the same at any depth.

Question 31

Why doesn’t the buoyant force on our bodies while we are standing in air cause us to float?

Answer 31

We weigh more than the weight of the air we displace.

Question 32

If 10 kg load on small piston with surface area A, how many load can be lifted by a hydraulic piston with a surface area of 50 A: a) 5 kg; b) 50 kg; c) 500 kg; d) 5000 kg.

Answer 32

c) 500 kg. 10 kg x 50 kg = 500 kg

Question 33

Bubbles are spherical for the reason of

Answer 33

surface tension.

Question 34

The air in this room has: a) mass; b) weight; c) energy; d) all of these; e) none of these.

Answer 34

d) all of these.

Question 35

Atmospheric molecules do not fly off into outer space because of

Answer 35

Earth gravitation.

Question 36

Atmospheric pressure is caused by the

Answer 36

weight of the atmosphere.

Question 37

Why don’t barometers use water instead of mercury?

Answer 37

Water can be used but the barometer will be too tall.

Question 38

About how high can water be theoretically lifted by a vacuum pump at sea level: a) less than 10.3 m; b) more than 10.3 m; c) 10.3 m.

Answer 38

c) 10.3 m.

Question 39

In drinking soda or water through a straw, we make use of: a) Atmospheric pressure; b) Bernoulli’s principle; c) Capillary action; d) Surface tension.

Answer 39

a) Atmospheric pressure.

Question 40

A piston in an airtight pump is withdrawn so that the volume of the air chamber is increased 3 times. What is the change in pressure: a) The pressure is 3 times the original pressure; b) The pressure is 1/3 the original pressure; c) The pressure does not change; d) There is not enough information to figure this out.

Answer 40

b) The pressure is 1/3 the original pressure. pV = Pv

Question 41

A balloon is buoyed up with a force equal to the

Answer 41

weight of air it displaces.

Question 42

A one-ton blimp hovers in the air. The buoyant force acting on it is

Answer 42

one ton.

Question 43

As a high-altitude balloon sinks lower and lower into the atmosphere, it undergoes a decrease in

Answer 43

volume.

Question 44

A bubble of air released from the bottom of a lake: a) becomes larger as it rises; b) alternately expands and contracts as it rises; c) becomes smaller as it rises; d) rises to the top at constant volume.

Answer 44

a) becomes larger as it rises.

Question 45

As a helium-filled balloon rises in the air, it becomes

Answer 45

less dense.

Question 46

The faster a fluid moves, the: a) greater its internal pressure; b) less its internal pressure; c) internal pressure is unaffected.

Answer 46

b) less its internal pressure.

Question 47

If water flows into a smaller diameter pipe and speeds up, the bubbles in the water: a) shrink; b) flatten; c) expand; d) wink.

Answer 47

c) expand.

Question 48

When you pass a speeding truck on a highway, your car’s pull toward the truck is explained by: a) Bernoulli’s Principle; b) Archimedes Principle; c) Boyle’s Law.

Answer 48

a) Bernoulli’s Principle.

Question 49

If you are standing in a cave on a cliff, and the air outside the cave is moving much faster than the air inside the cave, the pressure difference

Answer 49

wants to push you out of the cave.

Question 50

The most common state of matter in the universe is

Answer 50

plasma.