1. What is Specific Energy?

Definition: Specific energy is the energy per unit mass of a substance or system, measured in joules per kilogram (J/kg).

Purpose: It's a useful quantity in physics and engineering for comparing energy content of different materials or systems on a mass basis.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( SE \) — Specific Energy (Joules per kilogram, J/kg)
• \( E \) — Energy (Joules, J)
• \( m \) — Mass (kilograms, kg)

Explanation: The total energy is divided by the mass to determine how much energy is contained per unit mass.

3. Importance of Specific Energy

Details: Specific energy is crucial for comparing energy storage systems, fuel efficiency, and understanding material properties in various applications.

4. Using the Calculator

Tips: Enter the total energy in joules and mass in kilograms. Both values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What are some typical specific energy values?
A: Lithium-ion batteries: ~0.36-0.95 MJ/kg; Gasoline: ~46 MJ/kg; TNT: ~4.6 MJ/kg.

Q2: How is specific energy different from energy density?
A: Specific energy is per unit mass (J/kg), while energy density is per unit volume (J/m³).

Q3: Why use joules per kilogram instead of other units?
A: J/kg is the SI unit, making it universal for scientific calculations and comparisons.

Q4: Can specific energy be negative?
A: Normally no, as both energy and mass are positive quantities in this context.

Q5: Where is specific energy commonly used?
A: In battery technology, fuel comparisons, nutrition (calories per gram), and material science.