How to Use This Calculator
- Enter the current in milliamperes (mA) - this is the flow of electric charge per unit time.
- Enter the time in seconds for which the current flows.
- Click the "Calculate" button to compute the charge in milliampere-hours (mAh).
- The calculator also provides the charge in coulombs (C) for your reference.
Principle of Calculation
The calculator uses the formula:
Charge (mAh) = Current (mA) × Time (seconds) / 3600
This formula works because:
- 1 hour = 3600 seconds
- 1 milliampere-hour (mAh) is the charge transferred by a current of 1 milliampere flowing for 1 hour
- 1 coulomb (C) is the charge transported by a constant current of 1 ampere in 1 second
Practical Applications
This calculator is useful in:
- Estimating battery capacity requirements for electronic devices
- Designing power supply systems
- Calculating the energy storage capacity of capacitors
- Understanding the charge cycle of rechargeable batteries
Example Calculation
Suppose a device draws a current of 500 mA for 10 minutes:
- Convert time to seconds: 10 minutes × 60 seconds/minute = 600 seconds
- Calculate charge: 500 mA × 600 seconds / 3600 = 83.33 mAh
- This means the device uses approximately 83.33 mAh of charge