59 terms

# physical science final

just some terms from the practice final
###### PLAY
a passanger is in the rar seat of a car moving at a steady speed is at rest relative to
the front seat of the car
which distance can be most accurately measured with a ruler?
the width of a book
one kilometer equals 1000 meters. what does the prefix kilo- mean?
1000
a person walks 1 mile every day for exercise, leaving her front porch at 9:00 am. and returning to her front porch at 9:25 am. What is the total displacement of her daily walk?
0
a ball is rolled uphill a distance of 5 meters before it slows, stops, and begins to roll back. The ball rolls downhill 9 meters before coming to rest against a tree. What is the magnitude of the ball's displcaement?
4 meters
speed is the ratio of the distance an object moves to
the amount of time needed to travel the distance
instantaneous speed is measured
at a particular instant
a car traveled 60 km in 2 hours, 84 km in the next hour, and then 68 km in 2 hours before reaching its destination. What was the car's average speed?
148 km/h
the slope of a line on a distance-time graph is
speed
a horizontal line on a distance-time graph means the object is
moving at a constant speed
a distance-time graph indicates that an object moves 100 m in 4 s and then remains at rest for 6 s. What is the average speed of the object?
10 m/s
the rate at which velocity changes is called
acceleration
objects in free fall near the surface of the Earth experience
constant acceleration
suppose you increase your walking speed from 1 m/s to 3 m/s in a period of 1 s. What is your acceleration?
2 m/s to the second power
an object moving at 30 m/s takes 5 s to come to a stop. What is the object's acceleration?
-6 m/s to the second power
the slope of a speed-time graph indicates
acceleration
an object that is accelerating may be
slowing down, changing speed, gaining speed all these are correct
the SI unit of force is the
newton
when an unbalanced force acts on an object,
the object accelerates
when a pair of balanced forces acts on an object, the net force that results is
equal to zero
as you push a cereal box across a tabletop, the sliding friction acting on the cereal box
acts in the direction opposite of motion
the forces acting on a falling leaf are
gravity and air resistance
the property of matter that resists changes in motion is called
inertia
according to Newton's second law of motion, acceleration of an object equals the net force acting on the object divided by the object's
mass
if a force of 12 N is applied to an object with a mass of 2 kg, the object will accelerate at
6 m/s to the second power
mass times the acceleration due to gravity
the acceleration due to gravity on the surface of Mars is about one third the acceleration due to gravity on Earth's surface. The weight of a space probe on the surface of Mars is about
one third its weight on Earth's surface
Newton's third law of motion describes
action and reaction forces
the product of an object's mass and velocity is its
momentum
what is the momentum of a 50-kilogram ice skater gliding across the ice at a speed of 5 m/s?
250 kg.m/s
what is the unit of work?
joule
if you exert a force of 10.0 N to lift a box a distance of 0.9 m, how much work do you do?
9.0 J
if you perform 40 joules of work lifting a 10-N box from the floor to a shelf, how high is the shelf?
4.0 m
work is a transfer of
energy
the energy of motion is alled
kinetic energy
a small 20-kilogram canoe is floating downriver at a speed of 2 m/s. What is the canoe's kinetic energy?
40 J
a 4-kilogram cat is resting on top of a bookshelf that is 3 meters high. What is the cat's gravitational potential energy relative to the floor if the acceleration due to gravity is 9.8 m/s to the second power?
118 J
walking converts what type of energy into mechanical energy?
chemical
nuclear power plants are designed to convert nuclear energy into what type of energy?
electrical
Which of the following statements is true according to the law of conservation of energy?
energy cannot be created, energy cannot be destroyed, energy can be converted from one form to another, all are corrct
the study of Earth's composition, structure, and history is called
geology
the three main layers of Eath's interior are the
crust, mante, core
a naturally occurring, inorganic solid with a crystal structure and a characteristic chemical composition is a
mineral
rocks are classified as
igneous, metamorphic, sedimentary
intense heat, intense pressure, or reactions with hot water can modify a pre-existing rock to form a
metamorphic rock
a series of processes in which rocks are continously changed from one type to another called
the rock cycle
what changes are involved when mud from a lake bottom turns into sedimentary rock and then into a metamorphic rock?
compaction and cementation and then heat and pressure
the hypothesis taht the continents move slowly over Earth's surface and once were joined into one supercontinent is called
plate techtonics
new ocean crust is formed along
mid-ocean ridges
plates slide past each other, and crust is neither created nor destroyed, at a
transform boundary
stress in Earth's crust is caused by
plate movements
what is the name of the location within Earth where an earthquake begins
focus
in a diagram depicting the solar system as heliocentric, what is located at the center?
the sun
which of the following is the most likely reason that ancient observers believed taht Earth was the center of the universe?
objects in the sky appear to circle around Earth
the orbit of a planet around the sun is a
ellipse
which of the following objects does NOT orbit directly around the sun?
comets
what led to the discovery of three more planets than those that the ancient observers knew about?
the invention of the telescope in 1600
who was the first american in space
alan shepard
why does Earth's moon have no atmosphere?
there are no planets to release oxygen