Earth
The Greek mathematician Eratosthenes made measurements to show the size of _______.
Guides to thinking
Equations in Conceptual Physics are used mainly _______.
Not tested by science:
Hurricane Katrina was an act of God
Vince Young is the greatest quarterback of all time.
Hurricane Katrina was an act of God
Vince Young is the greatest quarterback of all time.
Tested by science:
Earth orbits the Sun every 365.25 days.
There will be a solar eclipse next Tuesday at 11 a.m.
People born under the sign of Sagittarius are twice as likely to be teachers as anyone else.
Mars once had liquid water on its surface.
Bacteria acquire resistance to antibiotics through changes in their DNA.
Listed following are a series of statements that each make a claim. Classify these as either testable by accepted methods of science or non-testable by accepted methods of science. Be sure to note that this question does not ask whether a statement would pass or fail a test; it only asks whether it is testable in principle.
A synthesis of well-tested ideas
A theory in science is ______.
An agreement between trained investigators
A fact in science is ______.
Wrong
A scientific hypothesis deemed valid must have a test for proving it ______.
Physics
Which of these is the most basic science?
Applying scientific discoveries
Technology is a tool for ______.
One of many ways of making discoveries
The scientific method of Galileo and Bacon is ______.
Spiritual world
Religion is concerned mainly with the ______.
He discovered that a ball rolling down an incline and onto a horizontal surface would roll indefinitely.
What was the greatest discovery by Galileo during his inclined-plane experiments?
A non-zero net force
Newton said that something was needed to change the motion of an object. A clear reading of his first law tells us that what is needed is ______.
Zero
What is the net force on a crate sliding at an unchanging speed when pushed with a steady force of 75 N?
In your hand
If while riding in a smooth-riding train, you toss a coin upward, the coin will normally land ______.
He demonstrated that light and heavy objects gain the same amount of speed when falling.
What did Galileo demonstrate in his Leaning Tower of Pisa experiment?
10 N
What is the net force when a pair of 5-N forces simultaneously act in the same direction on an object?
Newton’s first law
Which of Newton’s laws does the equilibrium rule illustrate?
200 N
How much support force acts on a 200-N girl standing on a weighing scale?
Time
Galileo’s definition of speed was a breakthrough because he is acknowledged to be the first to consider ______.
Direction
The difference between speed and velocity involves ______.
The same amount of speed each second
A ball rolling down an inclined plane each second picks up ______.
Change by the same amount each second
If an object moves with constant acceleration, its velocity must
100 m
A car accelerates at 2 meters/s/s. Assuming the car starts from rest, how far will it travel in 10 s?
None of the above
While a car travels around a circular track at a constant speed, its
inertia is zero.
acceleration is zero.
velocity is zero.
none of the above
An object covers a distance of 8 meters in the first second of travel, another 8 meters during the next second, and 8 meters again during the third second. Its acceleration in meters per second per second is approximately
It is always zero
What is the value of the velocity of the ball when it reaches its maximum height?
It is always negative
What is the acceleration of the ball when it is moving up, when it is at the maximum height, and when it is moving down? (Note: The acceleration graph is shown in red.)
110 km/h
While you are in a bus that moves at 100 km/h you walk from the back to the front at 10 km/h. What is your speed relative to the road outside?
Instantaneous speed
A speedometer normally measures ______.
Change in velocity per unit time
Which BEST describes what occurs when a body accelerates?
Acceleration
Galileo discovered that when air resistance can be neglected, all objects fall with the same ______.
30 m/s
A ball freely falling at 20 m/s will in the next second have a speed of ______.
Acceleration
When we are talking about how quickly “how fast” changes, we’re talking about ______.
It decreases
Use the “Force applied” slider to set the force applied on the elephant to somewhere in the middle of the range. After you have set the “Force applied” slider, do not change it again for this question. How would the acceleration change if the mass of the elephant were increased?
It increases
Use the “Mass of elephant” slider to set the mass of the elephant to somewhere in the middle of the range. After you have set the “Mass of elephant” slider, do not change it again for this question. How would the acceleration change if the applied force on the elephant were increased?
5 m
In its first second of free fall, a dropped softball will fall a vertical distance of ______.
6 m/s
Jogging Jake runs at 4 m/s along a train flatcar that moves at 10 m/s in the opposite direction. Jake’s speed relative to the ground is
6 m/s2
If a car increases its velocity from zero to 60 m/s in 10 seconds, its acceleration is
0 m/s2
An object covers a distance of 8 meters in the first second of travel, another 8 meters during the next second, and 8 meters again during the third second. Its acceleration is
The same
A rock dropped from a 5-m height accelerates at 10 m/s2 and strikes the ground 1 s later. If the rock is dropped from a height of 2.5 m, its acceleration of fall is
40 m/s
At one instant a heavy object in air is moving upward at 50 meters per second. One second later its speed is approximately
10 m/s
An apple falls from a tree and hits the ground 5 meters below with a speed of about
2 seconds
If a projectile is fired straight up at a speed of 10 m/s, the total time to return to its starting position is about
The same
A ball is thrown upwards and returns to the same location. Compared with its initial speed its speed when it returns is about
50 m/s
Neglecting air resistance, a ball projected straight upward so it remains in the air for 10 seconds needs an initial speed of
Velocity
Whenever a net force acts on an object, there is a change in the object’s _______.
Opposite to the direction of sliding
The direction of the force of friction on a sliding crate is _______.
Weight
Which depends on gravity?
Increases
As a skydiver gains speed in falling through the air, air resistance _______.
when the crate is pushed horizontally, whether sliding or not
A crate sits at rest on a factory floor. Friction between the crate and floor occurs _______.
Newton
The unit of mass is the kilogram, and the unit of weight is the _______.
inversely proportional to mass.
In considering proportions, acceleration is _______.
When units of newtons and kilograms are used for force and mass
When does the proportion form of Newton’s second law take the form of an equation?
6 N
A 10-N falling object encounters 4 N of air resistance. The net force on the object is
continue moving at 40 km/h.
You drive your car at a constant 60 km/h along the highway. You apply the brakes until the car slows to 40 km/h. If at that moment you suddenly release the brakes, the car tends to
1500 kg
A tow truck exerts a force of 3000 N on a car, which then accelerates at 2 m/s2. What is the mass of the car?
the tissue paper has too little mass to exert as much force on the boxer’s fist.
A boxer cannot exert much force on a piece of tissue paper suspended in air because _______.
the expelled gas pushing on the rocket
The force that propels a rocket is that provided by _______.
pushes harder on the floor while holding the rope
The team to win in a tug-of-war is the team that _______.
The magnitudes of both forces are the same.
A Volkswagen Bug and a Volvo truck have a head-on collision. Which statement is true??
5 N
A 7-N vector at an angle of 45° to the horizontal has a vertical component that is about _______.
are normally at right angles to each other
Force vector components for a sled pulled at an upward angle _______.
