Exam 1
The longest of the following is A) 0.00001 km. B) 0.001 ft. C) 1 mm. D) 0.01 in.
(A) 0.00001 km
The shortest of the following is A) 0.1 mi. B)10^4 m. C)10^3ft. D)10^4in.
(A)0.1 mi.
A meter is not equal to
0.01 km.
A centimeter is
0.01 m
Which one or more of the following pairs of displacements cannot be added to give a resultant displacement of 2 m?
1 m and 4 m
The prefix giga stands for
1,000,000,000
The number of cubic centimeters in a cubic foot is about
1.7 × 10^4 .
A ball whose momentum is mv strikes a wall and bounces off. The change in the ball's momentum is
2 mv
Arrange the following planets in the order of their distance from the sun. 1. Venus 2. Mars 3. Earth 4. Mercury
4, 1, 3, 2
A 50-kg person weighs
490 N
Which of the following sets of displacements might be able to return a car to its starting point?
60, 120, 180, and 240 km.
A sedentary person requires about 6 million J of energy per day. This rate of energy consumption is equivalent to about
70 W
Which of the following statements is true? A) The moon is chiefly responsible for the tides, with the sun's influence modifying the tidal range. B) The sun is chiefly responsible for the tides, with the moon's influence modifying the tidal range. C) High tides are caused by the sun, low tides by the moon. D) Low tides are caused by the sun, high tides by the moon.
A
Which one or more of the following is a vector quantity? A)angular momentum B)linear momentum C)kinetic energy D)potential energy E)Both A and B
Both A and B
The discovery that the planetary orbits are ellipses rather than circles was made by
Kepler
A planet that cannot be seen with the unaided eye is
Neptune.
The scientist who showed that gravity accounts for Kepler's laws of planetary motion was
Newton
A week is the time needed for
None of the choices are correct
The sun exerts a gravitational force on the earth and the earth exerts a gravitational force on the sun. The force the earth exerts
can be considered either as the action or as the reaction force.
The time needed for a planet to orbit the sun
depends on the average distance of the planet from the sun.
Relative to the stars, the moon seems to move
eastward
The stars in a constellation
form a pattern in the sky as seen from the earth
The speed of an object moving in a circle is doubled. The centripetal force needed is
four times as much as before.
If the moon were half as far from the earth as it is now, the gravitational force it exerts on the earth would be
four times its present value.
Stars and planets are round because
gravity forces them into this shape
When the sun, the earth, and the moon are all in line,
high tides are higher than usual and low tides are lower than usual
When first proposed, a scientific idea is usually called a
hypothesis.
The speed of a planet in its orbit
is highest when it is closest to the sun.
The escape speed needed for an object to leave the earth permanently
is more than the minimum speed it needs to become an earth satellite
Astrology
is nonsense
A hole is drilled to the center of the earth and a ball is dropped into it. When the ball is at the earth's center, compared with their respective values at the earth's surface
its mass is the same and its weight is 0.
A bullet is fired upward. As it rises,
its mass remains the same while its weight decreases
What distinguishes the scientific method from other ways of looking at the natural world is
its reliance on experiment and observation.
Which of the following is (are) not a unit of power? A)horsepower B)Newton-meter/second C)watt D)joule-second
joule-second
An object that has linear momentum must also have
kinetic energy
A regularity in observed data or a relationship between different quantities is usually called a
law
In the formula E0=mc^2, the symbol c represents the speed of
light
The length of the year is
more than 365 days
Scientific theories
must be constantly reviewed to see whether they are in accord with new experimental observations.
The period of the earth's orbit around the sun is
one year
A moving object does not necessarily have
potential energy
A rocket is fired in space. As it moves, the total momentum of the rocket and its exhaust gases 40
remains the same
Gravity is not
responsible for holding atoms and molecules together
In the distant past, the length of the day was
shorter than 24 hours
A golf ball and a ping-pong ball are dropped in a vacuum chamber. When they have fallen halfway down, they have the same
speed
In which one or more of the following is the earth assumed to be the center of the universe?
the Ptolemaic system
A day is the time needed for
the earth to turn completely on its axis.
Which of the following quantities is always the same to all observers? A)time intervals B)the speed of sound C)the speed of an object D)the speed of light
the speed of light
A year is the time needed for rev: 05_09_2014_QC_49368
the sun to migrate completely around the sky.
What never changes when two or more objects collide is
the total momentum of all the objects.
The British unit of length closest to the meter is the
yard