PS-6 Test Review What must increase to effect the KE of an object the most? The velocity because it is squared in the formula… KE= ½ mv 2

A car transfers chemical potential energy to _______ energy. Mechanical energy

What effects the GPE of an object?  Gravity, mass, & height

What is the SI Unit for energy  Joule (J)

 According to the law of conservation of energy, energy in the universe cannot be created or destroyed, therefore it is _________.  transferred

 How much work is done when a 10N force is applied over a 3 meter distance?  W = f x d = 10N x 3m = 30 J

 For an object to have KE, it must be________________.  moving

Where does a pendulum have:  Maximum KE?  Maximum PE?  Increasing KE?  Increasing PE?

What are the requirements to do work?  An object must move  The motion of the object must be in the same direction as the applied force on the object

You rub a balloon against your sweater:  What charge does the balloon have and why? Negative – it picked up electrons from your sweater  What charge does the sweater have and why? Positive – it has less electrons after transferring some to the sweater  By what method was charge transferred? friction

What is the difference?  Charge by conduction Charging an object by contact  Charge by induction Charging an object by holding a charged object near it  Which of the above is lightning and why? Charge by induction…the clouds and the ground don’t touch each other

What is static electricity?  The accumulation of excess electric charges on an object  Static meaning no motion

Electroscope  What does it detect? An unknown electric charge  When the leaves spread apart what has happened? The charges are the same and repel  How does it detect an unknown charge? leaves come together if the charges are different (attract)and will spread apart if like charges (repel)

Electric Current  What is it? The flow of electrons through a conductor  How is it measured? Amperes (A)  ______ is the force or push for electrons in a circuit and is measured in ______. Voltage, Volts (V)  ______ is electrical friction and is measured in _________. Resistance, Ohms ()

Ohm’s Law  What is it? The current in a circuit = voltage divided by the resistance  What is the current in a circuit with a 6 volt battery and 2 ohms of resistance? I = V/R = 6V / 2  = 3 A

Electric Circuits  A _______circuit has one path for electrons to flow. Series  A _______ circuit has more than one path for electrons to flow. Parallel

Series Circuit  What happens if a bulb is removed? All the lights go out – open circuit  If you add a bulb what happens to:  Voltage - increases  Current - decreases  Resistance - increases

Parallel Circuit  What happens if a bulb is removed? The other bulbs stay lit & are brighter  If a path is added, what happens to:  Voltage – Stays the same  Current - Increases w/ each path  Resistance – decreases w/ each path

 Resistance in a circuit is effected by what 3 things? Large diameter – less resistance Long wires – greater resistance Increase in temperature – increase resistance

Electromagnet  What is it? Electricity runs through a wire and causes a magnetic field  What can be done to increase it’s strength? Coil more wire around the object

 In electromagnetic induction, electric current is produced when a loop of wire is moved through a ___________. Magnetic field

What is the difference between AC and DC current?  AC =current moves back and forth  DC = flows in one direction

 A generator converts _______ energy to ________ energy. Mechanical / Electrical  An electric motor converts __________ energy to ________ energy. Electrical / Mechanical