Phys Test 3

The weight of a 1-square-meter column of air that extends from sea level to the top of the atmosphere is

101,000 N

A metal block has a density of 8 kg per cubic meter and a volume of 2 cubic meters. What is the block's mass?

16 kg

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

If one proton is removed from an ordinary helium nucleus, the result is

a heavy isotope of hydrogen

Inside a freely-falling runaway elevator, your

apparent weight is zero

The tides that occur when the sun, earth, and moon are at right angles to each other during a half moon

are neap tides and they are smaller than average

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

The pressure in a liquid depends on liquid

density and depth

When you float in fresh water, the buoyant force that acts on you is equal to your weight. When you float higher in the denser water of the Dead Sea, the buoyant force that acts on you is

equal to your weight

The main reason ocean tides exist is that the pull of the moon

is greater on oceans closer to the moon and less on oceans farther from the moon

Buoyant force is greatest on a submerged

is the same on each

The faster a fluid moves, the

less its internal pressure

How much gravitational force is there between two 1 kg steel balls placed 1 m apart from each other?

less than 0.00000000001 N

Which of these statements is true?

molecules are the smallest subdivision of matter that still retains chemical properties of a compound, atoms are not the smallest particles that exist, molecules are made up of about 100 distinct chemical elements

About what percentage of the molecules that make up the atmosphere are below an aircraft that flies at an altitude of 6 kilometers?

more than 50%

If each dimension of a steel bridge is scaled up ten times, its weight will be multiplied by about

one thousand, and its strength by one hundred

The weight of matter comes mostly from its

protons and neutrons

The smallest particle of those listed below is a

quark

Which of the following substances has a crystalline structure?

silver

Liquids

take the shape of their container

If a very strong wind blows past a large plate glass store window, the window may shatter because

the air pressure is reduced in the fast moving wind and the greater atmospheric pressure inside pushed the window out

A helium-filled ballon is released in the atmosphere. If it does not burst first, it will rise until

the ballon and surrounding air have equal densities

Consider two planets in space that gravitationally attract each other. If the masses of both planets are doubled, and the distance between them is also doubled, then the force between them is

the same

Which of the following is not a mixture?

water

You wish to bolt a sign to a horizontal I-beam supporting a bridge. You will weaken the beam least if you drill the bolt-holes through the

web (vertical part in the middle)