the total amount of energy before and after a chemical reaction is the same. Thus energy is
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
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
example of a change in motion that produces acceleration
a moving at a constant speed around a circular track
What is the reaction force and its reaction force
they are equal in magnitude but opposite in direction
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
Nuclear power plants are designed to convert nuclear energy into what type of 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
As a dropped penny falls toward the ground, ______ energy is converted to ______ energy
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
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.
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_____.
reactions such as cooking that result in products with more chemical energy than the reactants are ____.
the physical properties of a solution that differ from those of its solute and solvent include freezing point, boiling point, and _____.
The difference between speed and velocity is that velocity indicates the ______ of motion and speed does not.
The acceleration of a moving object is calculated by dividing the changes in _____ by the time over which the change occurs
If the forces acting on an object produce a net force of zero, the forces are called _____ _____
During a head-on auto collision, ____ causes a passenger in the front seat to continue moving ______.
The acceleration of an object us equal to the net ___ acting on the object divided by the object's ____.
If a gold ball and bowling ball are rolling at the same speed, the ____ ball has greater momentum.
When a pole-vaulter flexes the pole, the pole-vaulter increases the pole's ___ potential energy.
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.
"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 ____.
The electromagnetic waves with the longest wavelengths are _____ rays. The waves with the longest wavelengths are ____ waves.
The stored energy resulting from the relative positions of objects in a system is called ______.
White light from the sun actually contains all the visible wavelengths of the __________ _________.
Radio waves, microwaves, and infrared waves make up part of the ________ _______.
energy that lies at then level of atoms and that does not affect the motion on a large scale