Download presentation
Presentation is loading. Please wait.
Published byBeverly Franklin Modified over 5 years ago
1
Ohm’s Law
2
To calculate voltage, V: put your finger over V, this leaves you with I R, so the equation is V = I × R To calculate current, I: put your finger over I, this leaves you with V over R, so the equation is I = V/R To calculate resistance, R: put your finger over R, this leaves you with V over I, so the equation is R = V/I V I R Triangle
3
V=I x R V = voltage in volts (V) I = current in amps (A)
R = resistance in ohms (Ω) For most electronic circuits the amp is too large and the ohm is too small, so we often measure current in milliamps (mA) V=I x R
4
1 milliampere = amperes KHDMDCM or KHDADCM mA A
5
I=q/∆t I= intensity q= charge (C) ∆t= time interval Current Intensity
6
The light in the girls washroom requires a current of 40 amps
The light in the girls washroom requires a current of 40 amps. What is the charge needed for 60 seconds of electricity? I=q/∆t =40 A x 60s =2400 C Example
7
The microwave requires a current of 80 A
The microwave requires a current of 80 A. What is the charge needed to heat my lunch for 2 minutes? I=q/∆t =80 A x 120s =9600s Example 2
8
How many minutes has elapsed if 24000 C of charge pass through a circuit with a current of 1.6 A?
I=q/∆t 24000 = 1.6/ ∆t 24000/1.6 = ∆t =15000 s =250 minutes Example 3
9
What is the voltage across a 50 Ω resistor with a current of 400 mA?
400mA= 0.4 A V=IR V= 50 Ω x 0.4 A V= 20 volts Ohm’s
10
What is the resistance if a circuit has 228 volts and a current of 38 mA?
38 mA= A R = V/I R = 228 V / A R = 6000 Ω Ohm’s
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.