93 terms

# Science Final Exam

this is from the exam study guide Ms. Geesey gave the class
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the substances that undergo change in a chemical reaction are called
reactants
the arrow in a chemical equation means
forms, produces, yields
in a compound, chemical energy is contained in the
bonds
the total amount of energy before and after a chemical reaction is the same. Thus energy is
conserved
a student dissolved equal amounts of salt in equal amounts of warm water, room-temperature water, and ice water. what is true about this?
the salt dissolves most quickly in warm water
Some properties of an acid are
changes the color of an indicator, taste sour, usually reacts with metals
Examples of acidic foods:
lime, tomato, orange
what are some properties of a base?
feels slippery, tastes bitter, changes colors of indicators
A passenger in the rear seat of a car moving at a steady speed is at rest relative to
the front seat of the car
Speed is the ratio of the distance an object moves to
the amount if time needed to travel the distance
the slope of a line on a distance-time graph is
speed
a horizontal line on a distance-time graph means the object is
at rest
the rate at which velocity changes is called
accelaration
example of a change in motion that produces acceleration
a moving at a constant speed around a circular track
The slope of a speed-time graph indicates
accelaration
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
the property of matter that resists changes in motion is called
inertia
An orange might roll off your cafeteria tray when you stop suddenly because of
the orange's inertia
mass times the acceleration due to gravity
Newton's third law of motion describes
action and reaction forces
What is the reaction force and its reaction force
they are equal in magnitude but opposite in direction
Work is the transfer of
energy
What is transferred by a force moving an object through a distance?
energy
The energy of motion is called
kinetic energy
An object's gravitational energy is related to:
its height relative to a reference level, it mass, the acceleration due to gravity
Examples of an object with elastic potential energy:
a wind up toy that has been wound up, a compressed basketball, a stretched rubber band
Why is the gravitational potential energy of an object 1 meter above the moon's surface less than its potential energy 1 meter above Earth's surface?
the objects weight is more on the moon
the gravitational potential energy of an object is always measured relative to the
reference level from which the hieght is measured
When an object becomes warmer, this increases.
Thermal energy
The energy stored in gasoline is,
Chemical energy
Nuclear power plants are designed to convert nuclear energy into what type of energy?
electrical energy
Solar cells convert what type of energy into electrical energy?
electromagnetic energy
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
the mechanical energy of an object equals its
kinetic energy plus its potential energy
cellular telephones utilize
microwaves
At the top of its arc, a thrown ball has_____ potential
maximum
As a dropped penny falls toward the ground, ______ energy is converted to ______ energy
potential, kinetic
Example of mechanical energy?
potential energy
The primary source of the sun's energy is
nuclear fusion
The gravitational potential energy depends on
the mass of the object, the height, the acceleration due to gravity
The color that an object appears to be Whdepends on the
wavelengths of visible light that reaches your eyes
What device uses sound waves to view organs inside the body
sonogram
An apple appears red to your eye because it
reflects red light
the statement that in chemical reactions, the total mass of the reactants equals the total mass of the products is the law of ______.
conservation of mass.
An iron fence is unpainted, and it reacts and combines with the oxygen in the air, forming rust. The formation of rust is an example of an _____ reaction.
synthesis/ chemical
For a certain chemical reaction, the reactants contain 385 kJ of chemical energy, and the products contain 366kJ of chemical energy. In order for energy to be conserved, 19kJ of energy must be_____.
released (heat)
reactions such as cooking that result in products with more chemical energy than the reactants are ____.
endothermic
Chemical equations must be ____ to show that matter is conserved during the reaction.
balanced
the physical properties of a solution that differ from those of its solute and solvent include freezing point, boiling point, and _____.
conductivity
Stirring ____ the rate at which a solid will dissolve in a liquid.
increases
The motion of an object looks different to observers in different ___ _ _____.
points of reference
The SI unit for measuring ____ is the meter
distance
speed is measured in units of
meters per second
The difference between speed and velocity is that velocity indicates the ______ of motion and speed does not.
direction
The acceleration of a moving object is calculated by dividing the changes in _____ by the time over which the change occurs
velocity
A push or pull is an example of
force
The sum of all forces acting on an object is called the
net force
If the forces acting on an object produce a net force of zero, the forces are called _____ _____
balanced forces
The tendency of an object to resist change in it's motion is called ____.
inertia
During a head-on auto collision, ____ causes a passenger in the front seat to continue moving ______.
inertia, forward
The acceleration of an object us equal to the net ___ acting on the object divided by the object's ____.
force, mass
The force of gravity acting on an object is the object's ____.
weight
If a gold ball and bowling ball are rolling at the same speed, the ____ ball has greater momentum.
bowling
When you push on a wall, the ___ pushes back on you
wall
energy and work are measured on th SI unit called the ____.
joules
If the ___ of an object doubles, its kinetic energy doubles.
mass
Energy that is stored due to position or shape is called ____ energy.
potential
When a pole-vaulter flexes the pole, the pole-vaulter increases the pole's ___ potential energy.
elastic
You can calculate an object's gravitational potential energy by using the equation ______.
PE=mass x gravity x height
The sum of the kinetic energy ad potential energy of an object is called its _____ energy.
mechanical
Wind turbines convert ____ energy into electrical energy
kenetic
"energy cannot be created or destroyed" is a statement of the law of ______ __ ________
conservation of energy
When an apple falls from a tree to the ground, the apple's beginning kinetic energy and ending potential potential energy are both equal ____.
zero
The electromagnetic waves with the longest wavelengths are _____ rays. The waves with the longest wavelengths are ____ waves.
the formula for calculating kinetic energy can be written as _______.
KE= .5m x vsquared
The stored energy resulting from the relative positions of objects in a system is called ______.
potential
The electromagnetic waves with the highest energy are classified as _____ ____
gamma rays
_______ are used for cooking as well as for communication
microwaves
An ____ sensor can be used to measure the heat that objects radiate
infrared
White light from the sun actually contains all the visible wavelengths of the __________ _________.
electromagnetic spectrum
Radio waves, microwaves, and infrared waves make up part of the ________ _______.
electromagnetic spectrum
the sum of an object's kinetic and potential energies.
mechanical energy
energy due to motion
kinetic energy
the energy of an objects due to its position, shape, or condition
potential energy
energy that lies at then level of atoms and that does not affect the motion on a large scale
nonmechanical energy
EM waves that give off heat
infrared waves
EM waves that can carry telecommunication signals and cook food
microwaves
EM waves with high energy that can cause sunburn
ultraviolet rays
electromagnetic waves used in medicine to kill cancer cells and view bones
X-rays and gamma rays
EM waves used for television, AM, and FM radio signals