Science Workshop 4

Workshop 4 Physical Science

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Failures?

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Energy and Motion

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Vocabulary Force: a push or pull that causes an object to move, stop, or change direction.

Friction: a force that opposes, or acts against, motion when two surfaces rub against each other.

Magnetism: the force of repulsion (pushing) or attraction (pulling) between poles of magnets.

Gravitation: the force that pulls all objects in the universe toward one another.

Position: an object's place, or location.

Speed: a measure of the distance an object moves in a given amount of time.

Velocity: an object's speed in a particular direction.

Acceleration: a change in motion caused by unbalanced forces or a change in velocity.

Momentum: a measure of how hard it is to slow down or stop an object.

Orbit: the path one body in space takes as it revolves around another body; such as that of Earth as it revolves around the Sun. Law of Universal Gravitation: law that states that all objects in the universe are attracted to all other objects.

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Vocabulary Energy: the ability to cause change in matter.

Kinetic Energy: the energy of motion, or energy in use.

Potential Energy: the energy an object has because of its place or condition.

Electric Charge: the charge obtained by an object when it gains or loses electrons.

Electric Force: the attraction or repulsion of objects due to their charges.

Electric Current: the flow of electrons from negatively charged to positively charged objects.

Conductor: a material that conducts electrons easily.

Electric Circuit: the path along which electrons can flow.

Insulator: a material that does not carry electrons.

Resistor: a material that resists the flow of electrons in some way.

Electromagnet: a temporary magnet made by passing electric current through a wire coiled around an iron bar.

Reflection: the light energy that bounces off objects.

Refraction: the bending of light rays when they pass through a substance.

Lens: piece of clear material that bends, or refracts, light rays passing throue gh it.

Pitch: an element of sound determined by the speed at which sound waves move.

Volume: the amount of space that an object takes up; [sound], the loudness of a sound.

Temperature: the average kinetic energy of all the molecules in an object.

Heat: the transfer of thermal energy from one substance to another.

Conduction: the direct transfer of heat between objects that touch.

Convection: the transfer of heat as a result of the mixing of a liquid or a gas.

Radiation: the transfer of thermal energy by electromagnetic waves.

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FORCES

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Forces • A force is any push or pull that causes an object to move, stop, or change speed or direction.

• An object starts to move, stops moving, or changes speed or direction only when a force acts on it.

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Balanced and Unbalanced Forces Any object tends to conserve its speed and velocity unless an external force acts upon it.

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Friction, Magnetism, and Gravity • Three of the forces that affect objects on Earth every day are friction, magnetism, and gravity.

• Friction is a force that opposes, or acts against, motion when two surfaces rub against each other. Rough surfaces produce more friction than smooth surfaces do.

• Magnetism is the force of repulsion (pushing) or attraction (pulling) between poles of magnets. Every magnet has two poles, north and south. Every magnet has a magnetic field around it.

• Gravitation is the force that pulls all objects in the universe toward one another. This is the force that holds things to the surface of Earth. The strength of gravitation between two objects also depends on the distance between the objects and each other's masses.

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Gravity

Friction

Can you identify these forces?

Magnetism

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What is Gravity?

• Gravity is the force of attraction that any object that has mass exerts over other objects.

• Gravity depends on two factors: Mass and Distance.

Draw

Mass

Distance

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Free Fall Experiment

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Practical Applications of Forces

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MOTION

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Types of Motion SIMPLE

LINEAR

CIRCULAR

ORBIT

LINEAR CIRCULAR

SIMPLE

ORBIT

CIRCULAR

LINEAR

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ENERGY

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Kinetic and Potential Energy • Energy is the ability to cause changes in matter.

• There are two basic kinds of energy: the energy of motion, or energy in use, is kinetic energy. Any matter in motion has kinetic energy.

• Potential energy is the energy an object has because of where it is or because of its condition.

• The change of any object's energy back and forth between kinetic energy and potential energy is called the transformation of energy.

• Although energy often is transformed, or changed, from one form to another, the total amount of energy doesn't change.

• Energy can't be created or destroyed. This is the Law of Conservation of Energy.

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Kinetic

Kinetic Potential Kinetic Kinetic

Potential

Potential

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ACTIVITY Name as many types of Energy as you can and determine its type.

KINETIC

Eolic (Wind)

Solar Electric

POTENTIAL Elastic Nuclear Chemical

Mechanical

Sound Thermal Light

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Peru Our country almost all its electric energy from 2 sources: Hydroelectric plants and Thermal processes.

Electric energy consumption per person 1995‐2007

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LABS 1

Videos

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Resources How to do an Onion Epithelium Lab Activity.doc How to do a mouth and blood smear.doc

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Attachments

How to do an Onion Epithelium Lab Activity.doc How to do a mouth and blood smear.doc