2nd Exam
As the ball leaves the girl's hand, one second later it will have fallen
5 meters below the dashed line
A nucleus with an atomic number 44 and a mass number of 100 must have
56 neutrons
A ball tossed at an angle of 30º with the horizontal will go as far downrange as one tossed at the same speed at an angle of
60º
Which is larger: a lithium atom or fluorine atom?
A lithium atom
How fast does an electron move within an atom?
About 2 million m/s
Which is larger: an arsenic atom or a sulfur atom?
An arsenic atom
Distinguish between an atom and an element.
An element is made of only one type of atom.
Which of the following are incorrect statements about the atom?
Atoms are manufactured in plants, and in humans during pregnancy
Distinguish between these parts of a wave: period, amplitude, wavelength, and frequency.
Period: time between identical portions in waves. Amplitude: distance between midpoint and crest. Wavelength: distance between identical portions in waves. Frequency: how often a vibration occurs.
The vibrations along a transverse wave move in a direction _______.
Perpendicular to the wave
Earth is farther away from the Sun in June and closest in December. In which of these two months is Earth moving faster around the Sun?
The Earth travels faster about the Sun in December than in June.
How do we account for the great variety of substances in the world?
There are many possible combinations of atoms.
Rank the average gravitational forces from greatest to least between (a) the Sun and Mars, (b) the Sun and the Moon, and (c) the Sun and Earth.
(c)the Sun and Earth, (a)the Sun and the Moon, (b)the Sun and Mars
Suppose you stood on top of a ladder that was so tall that you were three times as far from Earth's center as you presently are. What would be your weight from its present value?
.11
List several common transition metals.
Tungsten, platinum, and iron
The Moon falls toward Earth in the sense that it falls _______.
beneath the straight-line path it would take without gravity
When a satellite travels at constant speed, its shape is a(n) _______.
circle
A satellite in elliptical orbit about Earth travels fastest when it moves _______.
close to Earth
If the mass of one planet somehow doubled, the force of gravity between it and neighboring planet would
doubles
When no air resistance acts on a fast-moving baseball, its acceleration is
downward, g
Which contributes more to an atom's size: electrons or protons?
electrons
Which electrons are most responsible for the properties of an atom?
electrons in the outermost shell
The elements fluorine, chlorine, and bromine are also known as _______.
halogens
If the period is doubled, the frequency is
halved
The atoms that make your body _______.
have existed since the start of the universe
When an elevator accelerates downward, your weight reading is
less
When a projectile achieves escape speed from Earth, it _______.
outruns the influence of Earth's gravity, but is never beyond it
When we consider the time it takes for a pendulum bob to vibrate up and down, we're talking about its _______.
period
A unit of light is the _______.
photon
Which contributes more to an atom's mass: electrons or protons?
protons
The atomic number of an element matches the number of
protons in the nucleus of an atom and electrons in a neutral atom
If the masses of two planets somehow doubled, the force of gravity between them
quadruples
The velocity of a typical projectile can be represented by horizontal and vertical components. Assuming negligible air resistance, the horizontal component along the path of the projectile
remains the same
When an astronaut in orbit is weightless, he or she is _______.
still in the grips of Earth's gravity
Does breathing cause you to lose or gain weight?
to lose weight
Does the medium in which a wave travels move with the wave?
No, the wave moves through the medium, which returns to its original position.
Isotopes are identified by their
atomic mass number
If the frequency of a particular wave is 20 Hz, its period is
1/20 second
Calculate the force of gravity on the 0.60-kgkg mass if it were 1.9×107 mm above Earth's surface (that is, if it were four Earth radii from Earth's center). F = G m1m2/d^2
F = 0.37 N
If the probe had been twice as massive, how would its weight on the comet surface have been affected?
Its weight would have been twice as high.
Earth is gravitationally pulled toward _______.
Jupiter, the Sun and Mars
The distance between adjacent peaks in the direction of travel for a transverse wave is its
Wavelength
Is there a limit to the number of electrons that can occupy a single shell?
Yes, because of the wave nature of electrons.
If you weigh yourself in an elevator, you'll weigh more when the elevator
accelerates upward
Newton did not discover gravity, for early humans discovered that whenever they fell. What Newton did discover is that gravity _______.
extends throughout the universe
An oscillating object takes 0.10 s to complete one cycle; that is, its period is 0.10 s. What is its frequency f?
f = 10 Hz
When an elevator accelerates upward, your weight reading on a scale is
greater
Suppose you are in an elevator. As the elevator starts upward, its speed will increase. During this time when the elevator is moving upward with increasing speed, your weight will be __________.
greater than your normal weight at rest
Suppose you are in an elevator that is moving upward. As the elevator nears the floor at which you will get off, its speed slows down. During this time when the elevator is moving upward with decreasing speed, your weight will be __________.
less than your normal weight at weight
When you toss a projectile sideways, it curves as it falls. It will be an Earth satellite if the curve it makes _______.
makes the curved surface of Earth
The force of gravity between two planets depend on their
masses and distance apart
An electron, when farther from the nucleus, has _______.
more potential energy
Consider a space pod somewhere between Earth and the Moon, at just the right distance so that the gravitational attractions to Earth and the Moon are equal. Is this location nearer Earth or the Moon?
nearer the Moon
Is it possible to see an atom using visible light?
no
A dropped ball accelerates as it falls. But a ball rolling on a horizontal surface has zero acceleration because _______.
no horizontal force acts on it
Consider a space probe three times as far from Earth's center as it would be at Earth's surface. Compared to at Earth's surface, its gravitational attraction to Earth at this distance is about _______.
one-ninth as much
Consider Earth and the Moon. As you should now realize, the gravitational force that Earth exerts on the Moon is equal and opposite to that which the Moon exerts on Earth. Therefore, according to Newton's second law of motion __________.
the Moon has a larger acceleration than Earth, because it has smaller mass
When we breathe, we inhale oxygen, O2, and exhale carbon dioxide, CO2, plus water vapor, H2O. Which likely has more mass: the air we inhale or the same volume of air we exhale?
the air we exhale
As you found in Part A, your weight will be greater than normal when the elevator is moving upward with increasing speed. For what other motion would your weight also be greater than your normal weight?
the elevator moves downward while slowing in speed
If you are standing on a scale in an elevator, what exactly does the scale measure?
the force you exert on the scale
A 2.0-mm-long wave oscillates 1.7 times each second. Find the speed of the wave. Wave speed = (frequency) x (wavelength)
v = 3.4 m/s
The speed of a satellite in an elliptical orbit
varies
Wave speed depends on frequency and what else?
wavelength
When the elevator cable breaks, the elevator falls freely so your weight reading is
zero