CH 4 Electric curcuits Flashcards
Voltage is another name for…
Potential difference
What name is given to the work done per coulomb of charge passing between two points
Voltage/ potential difference
What is potential difference measured in?
Volts (v )
What units are used to measure resistance?
Ohms
Karl measures the current through a resistor. What else will he need to measure in order to work out its resistance?
Voltage / potential difference
Resistance is equal to the potential difference divided by What?
Current
Calculate the potential difference if 20j of energy are transferred by 8C charge
2.5V
A battery provides a potential difference of 20v. What size current will flow through a 5 ohm resistor in this circuit
4A.
20V/5 ohm = 4A
A cell provides 6v to an LDR, the current through this LDR is measured and is found to be 3A. What is the resistance of the LDR
2 ohms
A battery provides a potential difference of 14V. What size current will flow through a 10 oHm resistor
1.4A
A circuit is set up to test two different resistors. Resistor 1 has a resistance of 4 ohms and resistor 2 has a resistance of 2 ohms. Which resistor will have the bigger current flowing through it, if the potential difference is constant.
Resistor 2
The higher the resistance, the more difficult it is for current to flow, so the lower the current will be. This means the resistor with lower resistance will have higher current
The potential difference across a variable resistor is 11v and the current flowing through is 0.4 A what is the present resistance of this variable resistor?
27.5 or 28 ohms
For a given potential difference, a bigger resistance means a smaller ________ through a component.
Current
What is the relationship between the current through a resistor and the potential difference across it at constant temperature?
Directly proportional
A current of 0.2A flows through a component with a resistance of 40 ohm. what’s the voltage?
8 volts
