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)