Current and Potential Difference Continued

Today: we revise the rule for electric current

We learn the rule for potential difference

In an electric c____, current is the flow of e_______. The bigger the current, the m___ electrons are flowing around the circuit. The w___ carry the electrons from one terminal

around the circuit to the other t______.

Current

lamps

ircuitlectrons ore

ireserminal

Measuring current I

Set up the circuit shown below……

…and then record the current using an ammeter in the places shown below.

What do you notice about the readings?The current is the same for each ammeter.In a series circuit the current is the same wherever you measure it.

When measuring current ammeters are always placed in series.

A

AA

The v_____ is a measure of how big a push the e_______ are given as they leave the cell or b_____. The bigger the voltage, the bigger the p___.

The cell, battery or p____ s_____ produces the voltage.

Voltage

lamps

oltagelectrons

atteryush

ower upply

Measuring voltage I

V2 V3

V1

Set up the apparatus as shown……

…then record the voltages at the locations shown.What do you notice about the readings?For a series circuit, the sum of the voltages for each component is equal to the voltage across the cell or battery.

V1 = V2 + V3

NB Voltmeters are connected in parallel

Voltmeter Voltage(V)

V1

V2

V3

1.50.750.75

Series circuit