Energy is the ability to do ____. Energy and Work Energy is the ability to do ____. Work is a transfer of __________ Energy is known by the changes it causes. Work is done when a force moves an object through a distance. Energy is transferred by a force moving an object through a distance. Both work and energy are typically measured in joules (J).

Energy has different forms. Energy and Work Energy has different forms. The sun gives off energy in the form of heat and light. Plants convert sunlight into food. People convert food energy into muscle movement.

The energy of motion is called __________energy. Kinetic Energy The energy of motion is called __________energy. The kinetic energy of any moving object depends upon the object’s mass and ____________. Doubling mass in the formula doubles the kinetic energy. Doubling speed quadruples the kinetic energy.

Kinetic Energy Calculating Kinetic Energy A 0.10-kilogram bird is flying at a constant speed of 8.0 m/s. What is the bird’s kinetic energy?

Kinetic Energy A 70.0-kilogram man is walking at a speed of 2.0 m/s. What is his kinetic energy? Answer:

Kinetic Energy 2. A 1400-kilogram car is moving at a speed of 25 m/s. How much kinetic energy does the car have? Answer:

Potential Energy Potential energy: energy that is stored as a result of position or ___________ Gravitational Potential Energy An object’s gravitational potential energy depends on mass,______, and the acceleration due to gravity. This type of potential energy increases when an object is raised to a higher level. Gravitational potential energy’s unit is joules.

Potential Energy This diver has gravitational potential energy as she stands at the end of a diving board. She gained the potential energy by doing work—by climbing up the steps to the diving board.

Potential Energy What is the potential energy relative to the water surface of a diver at the top of a 10.0-meter-high diving platform. Suppose she has a mass of 50.0 kilograms.

Potential Energy Elastic Potential Energy The potential energy of an object that is stretched or compressed is ________________potential energy. Something that is elastic springs back to its original shape after it is stretched or compressed.

The musician adds energy to the cello string by plucking it. Potential Energy When this musician pulls the string of her cello to one side, the string is stretched and gains potential energy. The musician adds energy to the cello string by plucking it. The energy stored in the stretched string is potential energy. The stored energy is converted into kinetic energy when the string is released and it vibrates.

Forms of Energy Each form of energy can be converted into other forms of energy. Mechanical Energy The energy associated with the motion and position of ______________________is mechanical energy. Mechanical energy is the sum of an object’s potential energy and kinetic energy. Mechanical energy is not limited to machines. Examples: speeding trains, bouncing balls, running athletes, etc.

Thermal Energy The total potential and kinetic energy of all the _____________ particles in an object make up its thermal energy. When an object’s atoms move faster, its thermal energy increases, and the object becomes warmer. This molten metal is extremely hot. It contains a great deal of thermal energy.

Chemical Energy The energy stored in chemical ____________. When bonds are broken, the released energy can do _____________. All chemical compounds, including fuels such as coal and gasoline, store energy. Chemical energy of burning wood produces thermal energy for heating marshmallows.

Electrical Energy The energy associated with electric ______________. Batteries and lightening are examples of electrical energy. Electromagnetic Energy The energy that travels through space in the form of ___________. Visible light and X-rays are examples of electromagnetic energy.

Nuclear Energy The nucleus of an atom is held together by strong and weak nuclear forces, which can store an enormous amount of potential energy. The energy stored in atomic nuclei is known as nuclear energy. Nuclear __________releases energy by splitting nuclei apart. Nuclear___________releases energy when less massive nuclei combine to form a more massive nucleus.