How To Find Electric Current Using Electric Charge And Time

Understanding electric current is crucial in various real-life applications such as charging devices, operating electrical appliances, and managing power systems. This article explains how to calculate electric current ($I$) when electric charge ($Q$) and time ($t$) are given. We will explore three relatable examples to illustrate the calculations.

Formula to Determine Electric Current

Electric current ($I$) can be calculated from the electric charge ($Q$) and the time ($t$) using the formula:

$$I={\displaystyle \frac{Q}{t}}$$

where:

• $I$ is the electric current (in amperes).
• $Q$ is the electric charge (in coulombs).
• $t$ is the time (in seconds).

Example 1: Determining the Charging Current for a Smartphone

Scenario: You know that $5400\text{C}$ of charge is delivered to your smartphone in $3\text{hours}$. What is the current provided by the charger?

Step-by-Step Calculation:

1. Convert Time to Seconds:

  $$t=3\text{hours}\times 3600\text{seconds/hour}$$

  $$t=10800\text{seconds}$$

2. Given:

  $$Q=5400\text{C}$$

  $$t=10800\text{seconds}$$

3. Substitute Values into the Electric Current Formula:

  $$I={\displaystyle \frac{Q}{t}}$$

  $$I={\displaystyle \frac{5400}{10800}}$$

4. Perform the Calculation:

  $$I=0.5\text{A}$$

Final Value

The charging current for the smartphone is:

$$I=0.5\text{A}$$

Example 2: Finding the Current for an Electric Car Charger

Scenario: An electric car receives $576000\text{C}$ of charge over $6\text{hours}$. What is the current supplied by the charger?

Step-by-Step Calculation:

1. Convert Time to Seconds:

  $$t=6\text{hours}\times 3600\text{seconds/hour}$$

  $$t=21600\text{seconds}$$

2. Given:

  $$Q=576000\text{C}$$

  $$t=21600\text{seconds}$$

3. Substitute Values into the Electric Current Formula:

  $$I={\displaystyle \frac{Q}{t}}$$

  $$I={\displaystyle \frac{576000}{21600}}$$

4. Perform the Calculation:

  $$I=26.67\text{A}$$

Final Value

The charging current for the electric car is:

$$I=26.67\text{A}$$

Example 3: Calculating the Current for a Household Appliance

Scenario: A household appliance uses $1200\text{C}$ of charge in $10\text{minutes}$. What is the operating current?

Step-by-Step Calculation:

1. Convert Time to Seconds:

  $$t=10\text{minutes}\times 60\text{seconds/minute}$$

  $$t=600\text{seconds}$$

2. Given:

  $$Q=1200\text{C}$$

  $$t=600\text{seconds}$$

3. Substitute Values into the Electric Current Formula:

  $$I={\displaystyle \frac{Q}{t}}$$

  $$I={\displaystyle \frac{1200}{600}}$$

4. Perform the Calculation:

  $$I=2\text{A}$$

Final Value

The operating current for the household appliance is:

$$I=2\text{A}$$

Summary

To find the electric current ($I$) given the electric charge ($Q$) and time ($t$), use the formula:

$$I={\displaystyle \frac{Q}{t}}$$

In the examples provided:

1. Charging a smartphone with $5400\text{C}$ over $3\text{hours}$ requires $0.5\text{A}$.

2. Charging an electric car with $576000\text{C}$ over $6\text{hours}$ needs $26.67\text{A}$.

3. A household appliance using $1200\text{C}$ in $10\text{minutes}$ operates at $2\text{A}$.

These calculations show how to compute the electric current in various practical situations, essential for evaluating power requirements and ensuring safe and efficient electrical operation.