Physical Science Practice Final
The charge on alkali metal ions is
+2
. Molecular motion in a gas is the minimum possible at
-273 ° C
The voltage needed to produce a current of 8 A in a resistance of 13 ohms is
104 V
Ocean waves whose period is 8 s are observed to have a wavelength of 100 m. Their speed is
12.5 m/s
The mass number of the nucleus 15 N is 7
15
The missing number in the equation ( )C4H10 + 13O2 → 8CO2 +10H2O is
2
The product of the alpha decay of the polonium isotope 210 Po is 84
206 Pb 82
A 1-kg object is moving at 20 m/s. To double its kinetic energy, its speed should be increased to approximately
28 m/s
An airplane reaches its takeoff speed of 60 m/s in 20 s starting from rest. The time it spends in going from 50 m/s to 60 m/s is
3.3 s
The number of moles of H2O formed when 1 mole of O2 reacts with C5H12 in the reaction C5H12 + 8O2 → 5CO2 + 6H2O is
3/4
The work done in lifting 10 kg of bricks to a height of 40 m on a building under construction is
4000 J
A net force of 100 N gives an object an acceleration of 2 m/s2. What net force would give the same object an acceleration of 1 m/s2?
50 N
The number of carbon atoms in a benzene ring is
6
The number of electrons shared among the carbon atoms in a benzene ring is
6
The number of calcium atoms in 1 mole of calcium is
6 × 1023
An airplane travels at constant speed for a distance of 600 km in a time of 20 min. Its speed is
600 km/hr
The number of neutrons in the nucleus 15 N is 7
7
A 3000-kg truck accelerates from 10 m/s to 30 m/s in 8 s. The net force on the truck is
7500 N
A square foot contains approximately
929 cm2
A double helix structure is characteristic of
DNA
The fundamental reaction of neutralization is
H++OH-→H2O
A proton has twice the de Broglie wavelength of an electron
The electron has the higher speed
Photosynthesis produces
carbohydrates
Of the following, the gas that contributes most to global warming is
carbon dioxide
The breakdown of the ozone layer is promoted by the emission into the atmosphere of
carbon dioxide from the burning of fossil fuels
Which of the following statements is true?
The moon is chiefly responsible for the tides, with the sun's influence modifying the tidal range
The discovery that the planetary orbits are ellipses rather than circles was made by
Kepler
The object in the sky that lies very nearly on an extension of the earth's axis is
Polaris
According to the uncertainty principle, it is impossible to precisely determine
both the position and the momentum of a particle
The particle easiest to remove from an atom is an
electron
Each dash in the structural formula of an organic molecule represents a shared
electron pair
The work output of every heat engine
equals the difference between its heat intake and heat exhaust
Chemical reactions that give off energy are called
exothermic
Air near the equator averages higher temperatures than air near the poles because
sunlight falls more nearly vertically at the equator than near the poles
An example of an ionic solid is
table salt
Kepler modified
the Copernican system
When a hydrogen atom is in its lowest energy level,
the de Broglie wavelength of its electron equals its orbit circumference
After 20 years, 150 g of an original sample of 200 g of a certain radioactive isotope has decayed. The half-life of the isotope is
10 years
A ship travels 60 km to the south and then 80 km to the east. The ship's displacement from its starting point is
100 km
When the temperature of a volume of air is equal to its dew point, the relative humidity of the air is
100%
An 80-dB sound relative to a 40-dB sound is more intense by a factor of
10000
When 100 kJ is removed from a 4-kg metal bar, its temperature drops from 200°C to 100°C. The specific heat of the metal is
0.16 kJ/kg. °C
A net horizontal force of 2000 N is applied to a 1000-kg car at rest. The car's speed after 6 s will be
0.3 m/s
A car starts from rest and reaches a speed of 12 m/s in 10 s. Its acceleration is
1.2 m/s2
A 60-kg woman climbs a hill 300 m high in 30 minutes. Her average power output during the climb is
10 W
In which one or more of the following is the earth assumed to be the center of the universe? A. the Ptolemaic system B. the Copernican system C. Kepler's laws of planetary motion D. Galileos system
A. the Ptolemaic system
Which of the following electron jumps in a hydrogen atom emits the photon of lowest frequency? A. n = 1 to n = 2 B. n = 2 to n = 1 C. n = 2 to n = 3 D. n = 5 to n = 4
B. n = 2 to n = 1
Which of the following statements is incorrect? A. All vector quantities have directions. B. All vector quantities have magnitudes. C. All scalar quantities have directions. D. All scalar quantities have magnitudes.
C. All scalar quantities have directions.
Which of the following statements is not true? A. Protons are positively charged. B. The proton mass is greater than the electron mass. C. The proton mass is almost the same as the neutron mass. D. A proton in an atom circulates around its nucleus.
C. The proton mass is almost the same as the neutron mass
Heat can be transferred through a vacuum by which one or more of the following? A. conduction B. convection C. radiation D. condensation
C. radiation
Which of the following is not a unit of work? A. Newton-meter B. Joule C. Kilogram-meter D. Watt-hour
D. Watt-hour
The highest of the following is/are: A. the summit of Mt. Everest. B. cirrus clouds. C. the ozone layer. D. the ionosphere.
D. the ionosphere
The electromagnetic waves emitted by a nucleus are called
a gamma ray
Relative to the radio signals sent out by a spacecraft headed away from the earth, the signals that are received on the earth have
a lower frequency
The ozone in the stratosphere
absorbs solar ultraviolet radiation
In a covalent compound
adjacent atoms share electron pairs
The bonds between the atoms in a molecule of a saturated organic compound are
all single
The nucleus of a helium atom is called
an alpha particle
The sun
attracts light waves passing nearby
The nucleus of an atom cannot be said to
be electrically neutral
Most solids are
crystalline
The properties of several different materials are being compared. If the samples all have the same mass, the one with the greatest volume also has the greatest
density
The time needed for a planet to orbit the sun
depends on the average distance of the planet from the sun
An example of a covalent solid is
diamond
The most active of the following nonmetals is
fluorine
The property of light waves that leads to the phenomenon of color is
frequency
Suppose there were molecules that had no attraction whatever for one another. A collection of such molecules would form a
gas
Protons and neutrons are held together to form nuclei by the
gravitational interaction
A vertical column in the periodic table is called a
group
Sound waves whose frequency is 300 Hz have a wavelength relative to sound waves in the same medium whose frequency is 150 Hz that is
half as great
When light is directed at a metal surface, the emitted electrons
have energies that depend upon the frequency of the light
Elements with similar properties (other than atomic mass)
have similar valence electron configurations
The second most abundant element in the universe is
hydrogen
A gas confined at 2 atmospheric pressures at room temperature is released from its container. What can be said of the total entropy after release compared to when confined in bottle?
increases
With increasing temperature, the solubility of a solid in a liquid
increases
According to the general theory of relativity, gravitation
is a distortion in space-time
The speed of a photon
is equal to the speed of light
Protons and electrons have different masses. When they are the same distance apart, the electric force between two electrons
is the same as the force between two protons
The upper limit to the speed of an object with mass
is the speed of light
When saturated air is warmed,
it becomes able to take up more water vapor
When a liquid freezes into a solid,
it gives off heat
Ice floats in water because
its density is less than that of water
When the speed of a moving object is doubled
its momentum is doubled
What distinguishes the scientific method from other ways of looking at the natural world is
its reliance on experiment and observation
When a planet is farthest from the sun in its orbit,
its speed is least
On a molecular level heat is
kinetic energy
High tides occur
less often than low tides
If a spaceship 100 m long when at rest on the earth were to travel at nine-tenths the speed of light, its length as measured by an observer on the earth would be
less than 100 m
The number of protons in a stable nucleus is always
less than or equal to the number of neutrons
The speed of the wave packet that corresponds to a moving particle is
less than the speed of light
Acids do not
liberate OH- ions when dissolved in water
A compass needle tends to
line up parallel to a magnetic field
The greater the decibel (dB) level of a sound wave, the
louder it is
The largest number of elements are classed as
metals
When 1 g of a metal is oxidized, the resulting oxide has a mass that is
more than 1 g
An example of an exothermic process is the
neutralization of an acid by a base
When a nucleus undergoes radioactive decay, its new mass number is
never more than its original mass number
Approximately 4/5 of dry air consists of
nitrogen
The isomers of a compound have different
structures
At an equinox, the noon sun is
overhead at the equator
Temperatures in the stratosphere increase with altitude because of the presence there of
ozone
A horizontal row in the periodic table is called a
period
In an electromagnetic wave, the electric field is
perpendicular to both the magnetic field and the wave direction
A molecule that has lost an electron becomes a
positive ion
The energy liberated in a chemical reaction comes from the
potential energy of atomic electrons
Amino acids are the basic units of
proteins
DNA controls the development and functioning of a cell by governing its manufacture of
proteins
When a substance gains electrons in a chemical reaction, the substance is said to be
reduced
On a rainy day the maximum frictional force between a car's tires and a certain level road surface is reduced to one quarter its usual value. The maximum safe speed for rounding a curve is
reduced to 71% of its usual value
A photon is emitted by an atom when one of the atom's electrons
shifts to a lower energy level
The higher the frequency of a sound wave, the
shorter its wavelength
In the distant past, the length of the day was
shorter than 24 h
The most active of the following metals is
sodium
Of the following kinds of waves, the ones that cannot travel through a vacuum are
sound waves
A magnetic field does not interact with a
stationary electric charge
An atomic nucleus has a mass that is
the same as the total mass of its constituent nucleons
The acceleration of gravity on the surface of Mars is 3.7 m/s2. Compared with his or her mass and weight on the earth, an astronaut on Mars has
the same mass and less weight
Which of the following quantities is always the same to all observers?
the speed of light
What never changes when two or more objects collide is
the total momentum of all the objects
Weather phenomena such as clouds and storms are found in the
troposphere
A sample of a gas is expanded to twice its original volume while its temperature is held constant. Relative to their original average energy, the new average energy of the molecules is
twice as great
The weakest bonds are
van der Waals
Relative to the gravitational force between two protons, the electric force between them is
weaker
The primary coil of a transformer is connected to a source of direct current of voltage V. The voltage of the secondary current is
zero