Learning package 2

Question 1

What is Ohm’s Law?

Answer 1

Relationship between voltage, resistance and current.

V = I x R

Question 2

What is power in an electrical circuit?

Answer 2

When electric current flows it generates heat. The rate at which heat is generated is the power.

Measures in Watts

Question 3

Equation for power

Answer 3

P = I x V

P=I2 x R

Question 4

What is a rheostat?

Answer 4

Variable resistor (value can be changed).

2 connections

Knob or slider varies resistance

Question 5

What is a penentiometer?

Answer 5

Variable resistor.

Has 3 connections

Question 6

What is an open circuit?

Answer 6

Break in the wire/flow of electrons.

Question 7

Resistors have four coloured bands. What do they represent?

Answer 7

Band 1 & 2 - form a number
Band 3 - is multiplied by the band 1&2 # to the power of 10
Band 4 - is the tollerance

Question 8

What is the difference between series and parallel circuits?

Answer 8

Series has 1 direction of flow.

Parallell has more than one direction flowing through branches

Question 9

How to calculate current and resistance on a series curcuit.

Answer 9

Current is constant in a series circuit.

All resistors are added up to equal Req.