1 Answer
A step-up transformer is a device used to increase the voltage of an electrical signal. Hereβs how it works:
### 1. **Basic Structure:**
A transformer consists of two coils of wire:
* **Primary coil**: This is connected to the input voltage source (the one that provides the electricity).
* **Secondary coil**: This coil gives the output voltage (which is higher in a step-up transformer).
Both coils are wound around a core made of magnetic material, usually iron, which helps to transfer energy between them.
### 2. **The Principle of Operation:**
Transformers work based on **Faraday's Law of Induction**, which states that a changing magnetic field induces an electric current in a coil.
* When alternating current (AC) flows through the primary coil, it creates a changing magnetic field around it.
* This changing magnetic field then induces a current in the secondary coil.
### 3. **Voltage Transformation:**
The voltage increase or decrease depends on the ratio of turns (loops of wire) in the primary coil to the secondary coil.
* In a **step-up transformer**, the secondary coil has **more turns** of wire than the primary coil.
* The voltage is increased because the secondary coil "captures" more of the energy from the changing magnetic field, leading to a higher voltage at the secondary side.
### 4. **Voltage and Current Relationship:**
The relationship between the voltage and current in the primary and secondary coils is given by the following formulas:
* Voltage ratio:
$$
\frac{V_{\text{secondary}}}{V_{\text{primary}}} = \frac{N_{\text{secondary}}}{N_{\text{primary}}}
$$
(where $V$ is voltage, and $N$ is the number of turns)
* Current ratio:
$$
\frac{I_{\text{secondary}}}{I_{\text{primary}}} = \frac{N_{\text{primary}}}{N_{\text{secondary}}}
$$
(where $I$ is current)
In a step-up transformer, since the secondary has more turns, the voltage increases, but the current decreases proportionally.
### 5. **Energy Conservation:**
Despite the change in voltage and current, the total power (neglecting losses) remains the same. Power is given by:
$$
P = V \times I
$$
So, if the voltage goes up, the current goes down to keep the power constant.
### Example:
If a step-up transformer has a primary coil with 100 turns and a secondary coil with 1000 turns, and the input voltage is 100V, the output voltage will be:
$$
V_{\text{secondary}} = 100V \times \frac{1000}{100} = 1000V
$$
### Conclusion:
A step-up transformer increases voltage and decreases current. It's commonly used in power transmission to send electricity over long distances efficiently, as higher voltage allows for lower current and reduces energy losses.
### 1. **Basic Structure:**
A transformer consists of two coils of wire:
* **Primary coil**: This is connected to the input voltage source (the one that provides the electricity).
* **Secondary coil**: This coil gives the output voltage (which is higher in a step-up transformer).
Both coils are wound around a core made of magnetic material, usually iron, which helps to transfer energy between them.
### 2. **The Principle of Operation:**
Transformers work based on **Faraday's Law of Induction**, which states that a changing magnetic field induces an electric current in a coil.
* When alternating current (AC) flows through the primary coil, it creates a changing magnetic field around it.
* This changing magnetic field then induces a current in the secondary coil.
### 3. **Voltage Transformation:**
The voltage increase or decrease depends on the ratio of turns (loops of wire) in the primary coil to the secondary coil.
* In a **step-up transformer**, the secondary coil has **more turns** of wire than the primary coil.
* The voltage is increased because the secondary coil "captures" more of the energy from the changing magnetic field, leading to a higher voltage at the secondary side.
### 4. **Voltage and Current Relationship:**
The relationship between the voltage and current in the primary and secondary coils is given by the following formulas:
* Voltage ratio:
$$
\frac{V_{\text{secondary}}}{V_{\text{primary}}} = \frac{N_{\text{secondary}}}{N_{\text{primary}}}
$$
(where $V$ is voltage, and $N$ is the number of turns)
* Current ratio:
$$
\frac{I_{\text{secondary}}}{I_{\text{primary}}} = \frac{N_{\text{primary}}}{N_{\text{secondary}}}
$$
(where $I$ is current)
In a step-up transformer, since the secondary has more turns, the voltage increases, but the current decreases proportionally.
### 5. **Energy Conservation:**
Despite the change in voltage and current, the total power (neglecting losses) remains the same. Power is given by:
$$
P = V \times I
$$
So, if the voltage goes up, the current goes down to keep the power constant.
### Example:
If a step-up transformer has a primary coil with 100 turns and a secondary coil with 1000 turns, and the input voltage is 100V, the output voltage will be:
$$
V_{\text{secondary}} = 100V \times \frac{1000}{100} = 1000V
$$
### Conclusion:
A step-up transformer increases voltage and decreases current. It's commonly used in power transmission to send electricity over long distances efficiently, as higher voltage allows for lower current and reduces energy losses.