Exam 1
A
A 10-N falling object encounters 10 N of air resistance. The net force on the object is A) 0 N. B) 4 N. C) 6 N. D) 10 N. E) none of the above
Mass
A Measure of Inertia
A
Action and reaction forces comprise the parts of A) a single interaction. B) two interactions.
B
An object is pulled northward with a force of 10 N and southward with a force of 15 N. The magnitude of the net force on the object is A) 0 N. B) 5 N. C) 10 N. D) 15 N.
A
E) none of the above Which direction does a table push a book resting on it? A) up B) left C) right D) down
B
If a car increases its velocity from zero to 60 km/h in 10 s, its acceleration is A) 3 km/h ∙ s B) 6 km/h ∙ s C) 10 km/h ∙ s D) 60 km/h ∙ s E) 600 km/h ∙ s
Mass
Quantity of matter in an object The measure of inertia or sluggishness that an object exhibits in response to any effort made to start it, stop it or change its state of motion in any way
Volume
The amount of space an object takes up
Acceleration
The rate at which velocity changes
proportional
Weight and mass are ____________.
C
Which has the greatest density? A) 1 kg of feathers B) 10 kg of feathers C) 1 kg of lead
a. snail growth/population growth, b. temperature of the different locations, c. species of snail, beginning population size, snail container size, etc.
Your younger sister has decided to raise aquatic snails and get rich. She observes that the snails she secretly keeps in her bedroom windowsill seem to grow faster than the snails she keeps in the windowsill of the shed in the backyard. The windows both face the same direction so the algae growth (snail food) should be the same in each but the temperature is much warmer in her room. a) Identify the dependent variables (outcome/data) b) Identify the independent (manipulated) variable c) Identify possible variables to control/keep constant
greater, smaller
___ MASS = ___ INERTIA ___ mass= ___ inertia
small large small
___ net force, __ mass = ___ acceleration
Law
a general hypothesis or statement about the relationship of natural quantities that have been tested over and over again and has not been contradicted—also known as a principle
Fact
a phenomenon about which competent observers can agree
Theory
a synthesis of a large body of information that encompasses well-tested hypotheses about certain aspects of the natural world
Mass
involves how much matter an object contains. (lbs, grams, kilograms)
free fall
the motion of a falling object when the only force acting on it is gravity
Law of Action-Reaction
For every action there is an equal and opposite reaction
Density
is the measure of how much mass occupies a given space.
instantaneous speed
the speed of an object at one instant of time
Law of Inertia (Newton's First Law of Motion)
the velocity of an object does not change unless a force is applied.
average speed
total distance divided by total time
kg
10 newtons = 1___
Force
A push or a pull
Speed
The distance an object travels per unit of time
Friction
A force that opposes motion between two surfaces that are in contact
B
A kilogram is a measure of an object's A) weight. B) force. C) mass. D) gravity. E) center of mass.
B
An apple falls from a tree and hits the ground 5 m below. It hits the ground with a speed of about A) 5 m/s. B) 10 m/s. C) 15 m/s. D) 20 m/s. E) not enough information given to estimate
Law of Acceleration (Newton's 2nd Law)
An object will move in the direction of the force applied to it.
C
Disregarding air resistance, objects fall at constant A) velocity. B) speed. C) acceleration. D) distances each successive second.
Principle of Falsifiability
For a hypothesis to be considered scientific, it must be testable—it must, in principle, be capable of being proved wrong.
B
If a freely falling object were somehow equipped with a speedometer, its speed reading would increase each second by about A) 5 m/s. B) 10 m/s. C) 15 m/s. D) a variable amount E) depends on its initial speed
B
If an object's mass is decreasing while a constant force is applied to the object, the acceleration A) decreases. B) increases. C) remains the same.
B
If the mass of an object does not change, a constant net force on the object produces constant A) velocity. B) acceleration. C) both A and B D) none of the above
B
On the surface of Jupiter, where the acceleration due to gravity is about three times that of Earth, a 100-kg rock would have a weight of about A) 1000 N. B) 3000 N. C) 6000 N. D) 9000 N.
C
One object has twice as much mass as another object, and also has twice as much A) inertia. B) velocity. C) gravitational acceleration. D) volume. E) all of the above
C
One-half second after starting from rest, a freely falling object will have a speed of about A) 20 m/s. B) 10 m/s. C) 5 m/s. D) 2.5 m/s. E) none of the above
kilogram
SI unit for mass
A
Strange as it may seem, it is just as hard to accelerate a car on the Moon as it is to accelerate the same car on Earth. This is because the A) mass of the car is independent of gravity. B) weight of the car is independent of gravity. C) Nonsense! A car is much more easily accelerated on the Moon than on Earth.
D
The scientific method is a method for A) making hypotheses. B) gaining new knowledge. C) making observations. D) testing theories. E) designing experiments.
D
The statement, "There are regions beneath Earth's crust that will always be beyond the reach of scientific investigation," is a A) fact. B) speculation. C) hypothesis. D) scientific statement. E) theory.
B
The synthesis of a large collection of information that contains well-tested and verified hypotheses about certain aspects of the world is known as a scientific A) fact. B) hypothesis. C) law or principle. D) theory. E) none of the above
Inertia
The tendency of an object to resist a change in motion
D
a heavy rock and a light rock in free-fall have the same acceleration. The reason the heavy rock doesn't have a greater acceleration is that the A) force due to gravity is the same on each. B) air resistance is always zero in free fall. C) inertia of both rocks is the same. D) ratio of force to mass is the same. E) none of the above
Weight
the amount of gravitational pull on an object
