Step one: Calculate first the total resistance of the circuit: The equivalent resistance for R2 and R3 is: R2-3 = 1/R2 + 1/R3 = 7.2ohms R total = R1+ R23 = 10ohms + 7.2 ohms = 17.2 ohmsStep two: Calculate the Total Current V/R=I I1 = 30V / 17.2 Ohms = 1.74 Amp. (Since R1 is in series connection, the total current is the same for that path).Step three- calculate voltage drop across each resistor To Calculate the voltage drop for R1 you: VR1 = 1.74 Amp x 10 ohms = 17.4 volts Calculate the voltage drop across R2 and R3. Since the equivalent resistance for R2 and R3(R23) as calculated above is 7.2 ohmsStep 4- We can now calculate the voltage across each parallel resistor.Calculate the total voltage across R23 using IxR=V 1.74 x 7.2 = 12.528V, we can now calculate the individual current for R2 and R3I2 = VR2 / R2 = 12.5 volts / 18ohms = 0696 Amp. I3 = VR3 / R3 = 12.5 volts / 12ohms = 1.044 Amp.
Calculating Voltage drop
Caption: : You can check your answer by adding I2 and I3 together and it should be the same as I1
a)
Calculate
the current in each resistor
Step 1- calculate
the total resistance
1/R2 +1/R3= 1/R23
1/6 + 1/3 =1/R23
0.167 + 0.333=
1/0.500
R23 =2 ohms
R1+ R23= 6 ohms=
Total Resistance
Step 2: find the
current of the circuit
I= V/R = 24/6
=0.004A (convert to mA to make a whole number, x 10 to the power 3) =4mA
Step 3: IR1 x R3 4mA x 3000 (converting from
kiloOhms to Ohms) R2 + R3
6000+3000
=1.33mA
Step 4: IR1 x
R2 = 4mA x 6000 R2+R3 6000 + 3000
=2.67mA
Slide 3
a)
The power input to the circuit.
Power = V X I
Power= 24 x 4
Power= 96mW
b)
The power consumed by each resistor
Power = I squared x R
Resistor 1= 4 (squared) x 4 =64mW
Resistor 2= 1.33(squared) x 6 = 10.61 mW
Resistor 3= 2.67(squared) x 3 =21.39 mW
a) Calculate the current in resistor R2 Step one: calculate total resistance of R1 and R2 in order to turn the circuit into a series. In order to find total resistance you do: 1/R1 + 1/R2 = 1/R12 ¼ + 1/6= 1/R12 0.25 +0.17 = 0.417 (0.42) 1/0.42 =2.38 =2.4Ohms R12= 2.4 Step two: now you have the total resistance through R1 and R2 you have to find the total resistance of the circuit, by adding R12 and R3 together R12 + R3 =TR 2.4 + 9.6= 12 OhmsStep 3- to find the current in the circuit you need to divide the voltage by Resistance V /R = I 36 / 12 = 3A Step 4- you then need to find the voltage going through R12.V= I X R12V= 3 x 2.4V= 7.2 V Step 5- to calculate the current of resistor 2 you have to use the information we have found above and put the figures into the equation I= V / R7.2 / 6 =1.2A So current in resistor 2 is 1.2A
Slide 6
Step 4- you then need to find the voltage going through R12.V= I X R12V= 3 x 2.4V= 7.2 V Step 5- to calculate the current of resistor 2 you have to use the information we have found above and put the figures into the equation I= V / R7.2 / 6 =1.2A So current in resistor 2 is 1.2A
Slide 7
a) Calculate the power consumed in R1
Power = voltage(squared) x Current
Step one: find out the current in R1
V /R1 = I
7.2 / 4 = 1.8A
Current in R1 =!.8A
Step two: now we know the current we can use our formula of
power= Current (squared) x Resistance
I(squared) x R1 = P is the same as:
1.8A(squared) x 4 = P
P=12.96W
