# GCSE Physics

 What is the symbol for a switch What is the symbol for a key What is the symbol for a cell What is the symbol for a battery What is the symbol for a diode What is the symbol for a resistor what is the symbol for a variable resistor What is the symbol for an LED what is the symbol for a lamp  what is the symbol for a fuse Wheat is the symbol for a voltmeter What is the symbol for a thermistor what is the symbol for an ammeter what is the symbol for an LDR Current flowing through a component in a circuit is measured in  Amperes (A) using an ammeter connected in a series with a component  The current through a component depends on  It's resistance  The greater the resistance the ...... The current per a given p.d. Across the component  Lower  Adding extra bulbs in series add  Extra resistance this decreases the current  The p.d. Across a component is measured in  Volts (V) using a voltmeter  The p.d. Provided by cells connected in a series is the Sum of the p.d. Of each cell (depending on the direction in which they are connected) The resistance of a component can be found by measuring the Current through and the potential difference across the component for formula is I = V/R V represents the Potential difference and th unit is volts (V) I represents the Current and the unit is amperes (A) R represents Resistance and the units are ohms If the resistance is 5 and the current is 10 what is p.d. I = V/R 5 = V/105 * 10 = V 50 V = V if  the resistance is 25 and the p.d. is 100 what is the current I = V/R I = 100/25 I = 4 A  if the current is 1.5 and the p.d. is 3 what is the resistance I = V/R 1.5 = 3/R 1.5R = 3 R = 3/1.5 R = 2 ohms  the p.d. across a compnent in a circuit is measured in  volts (V) using a voltmeter connected across the component  ammeters are always connected in  series even in a parallel circuit voltmeters are always connected in  parallel with a compenent even in a series circuit  the p.d. provided by cells connected in a series is  the sum of the p.d. of each cell (depending on the direction in which they are connected) Authorghoran ID172791 Card SetGCSE Physics DescriptionRevision Updated2012-09-24T05:15:59Z Show Answers