What Is the Resistance and Power for 24V and 4.8A?

24 volts and 4.8 amps gives 5 ohms resistance and 115.2 watts power. Ohm's Law (V = IR) and the power equation (P = VI) connect all four electrical values. Knowing any two lets you calculate the other two instantly.

24V and 4.8A
5 Ω   |   115.2 W
Voltage (V)24 V
Current (I)4.8 A
Resistance (R)5 Ω
Power (P)115.2 W
5
115.2

Formulas & Step-by-Step

Resistance

R = V ÷ I

24 ÷ 4.8 = 5 Ω

Power

P = V × I

24 × 4.8 = 115.2 W

Verification (alternative formulas)

P = I² × R

4.8² × 5 = 23.04 × 5 = 115.2 W

P = V² ÷ R

24² ÷ 5 = 576 ÷ 5 = 115.2 W

Circuit Analysis

Heat Dissipation

This circuit dissipates 115.2 watts of power as heat. In a resistor, all electrical energy at steady state converts to thermal energy. The actual component power rating needs headroom above this steady-state figure, but the specific derating depends on resistor type (carbon-comp, metal-film, wirewound each behave differently), ambient temperature, airflow or heat-sinking, and whether the load is continuous or pulsed. Check the resistor datasheet for the manufacturer-specific derating curve rather than applying a blanket margin.

If You Change the Resistance

ResistanceCurrentPowerChange
2.5 Ω9.6 A230.4 WLower R = more current
3.75 Ω6.4 A153.6 WLower R = more current
5 Ω4.8 A115.2 WCurrent
7.5 Ω3.2 A76.8 WHigher R = less current
10 Ω2.4 A57.6 WHigher R = less current

Same Resistance at Different Voltages

Holding the resistance constant at 5Ω, here is how current and power scale with source voltage. This is a reference table, not a set of separate circuit scenarios: each row is the same resistor under a different applied voltage.

VoltageCurrent (at 5Ω)Power
5V1 A5 W
12V2.4 A28.8 W
24V4.8 A115.2 W
48V9.6 A460.8 W
120V24 A2,880 W
208V41.6 A8,652.8 W
230V46 A10,580 W
240V48 A11,520 W
480V96 A46,080 W

Frequently Asked Questions

R = V ÷ I = 24 ÷ 4.8 = 5 ohms.
P = V × I = 24 × 4.8 = 115.2 watts.
Wire sizing for a given current is not an Ohm's Law calculation. It depends on run length, source voltage, voltage-drop target, conductor material, insulation and termination temperature rating, cable type, and ambient and bundling conditions. The dedicated wire-size calculator takes those variables as input.
All 115.2W is dissipated as heat in a pure resistor at steady state. The component power rating needs headroom above this steady-state figure, but the specific derating depends on resistor type (carbon-comp, metal-film, wirewound each behave differently), ambient temperature, airflow or heat-sinking, and whether the load is continuous or pulsed. Check the resistor datasheet for the manufacturer-specific derating curve.
Ohm's Law (V = IR) and the power equation (P = VI) connect all four. Given any two, you can calculate the other two.
This calculator provides estimates for reference purposes only. Always consult a licensed electrician and verify compliance with the National Electrical Code (NEC) and local electrical codes before performing any electrical work.