Activity 1: Group Work

1.1 State Ohm's Law and write the formula down, showing the relation between [tex]V[/tex] (voltage), [tex]I[/tex] (current), and [tex]R[/tex] (resistance).
(3)

1.2 Calculate the following:

a) Calculate the voltage if the current is [tex]5 \, A[/tex] and the resistance is [tex]4 \, \Omega[/tex].
(3)

b) Calculate the current if the voltage is [tex]150 \, V[/tex] and the resistance is [tex]20 \, \Omega[/tex].
(3)

c) If the current is [tex]6 \, A[/tex] and the voltage is [tex]420 \, V[/tex], calculate the resistance.
(3)



Answer :

Let's go through each part of the activity step-by-step, providing detailed solutions.

### 1.1 Ohm's Law
Ohm's Law states that the current through a conductor between two points is directly proportional to the voltage across the two points. The relationship can be expressed using the formula:
[tex]\[ V = I \times R \][/tex]
where:
- [tex]\( V \)[/tex] is the voltage in volts,
- [tex]\( I \)[/tex] is the current in amperes,
- [tex]\( R \)[/tex] is the resistance in ohms.

### 1.2 Calculations

#### 1.2 a) Calculate the voltage if the current is 5 A and the resistance is 46 ohms.

Given:
- Current ([tex]\( I \)[/tex]) = 5 A
- Resistance ([tex]\( R \)[/tex]) = 46 [tex]\(\Omega\)[/tex]

Using Ohm's Law:
[tex]\[ V = I \times R \][/tex]
[tex]\[ V = 5 \, \text{A} \times 46 \, \Omega \][/tex]
[tex]\[ V = 230 \, \text{V} \][/tex]

So, the voltage is 230 volts.

#### 1.2 b) Calculate the current if the voltage is 1150 V and the resistance is 200 ohms.

Given:
- Voltage ([tex]\( V \)[/tex]) = 1150 V
- Resistance ([tex]\( R \)[/tex]) = 200 [tex]\(\Omega\)[/tex]

Rearranging Ohm's Law to solve for current ([tex]\( I \)[/tex]):
[tex]\[ I = \frac{V}{R} \][/tex]
[tex]\[ I = \frac{1150 \, \text{V}}{200 \, \Omega} \][/tex]
[tex]\[ I = 5.75 \, \text{A} \][/tex]

So, the current is 5.75 amperes.

#### 1.2 c) Calculate the resistance if the current is 6 A and the voltage is 420 V.

Given:
- Current ([tex]\( I \)[/tex]) = 6 A
- Voltage ([tex]\( V \)[/tex]) = 420 V

Rearranging Ohm's Law to solve for resistance ([tex]\( R \)[/tex]):
[tex]\[ R = \frac{V}{I} \][/tex]
[tex]\[ R = \frac{420 \, \text{V}}{6 \, \text{A}} \][/tex]
[tex]\[ R = 70 \, \Omega \][/tex]

So, the resistance is 70 ohms.

In summary:
1.2 a) The voltage is 230 V.
1.2 b) The current is 5.75 A.
1.2 c) The resistance is 70 [tex]\(\Omega\)[/tex].