Impulse Accumulates over a Time Window - Electromagnetic Radiation Pressure and Momentum Step by Step

A finite radiation force over time gives exact impulse. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.

highlighted = computed this step

Impulse accumulates over time

The force source and time window determine the impulse.

J=Ft=3\cdot 4=12\ \text{kg}\,\text{m}/\text{s}

The time window is finite

No continuous pressure history is assumed.

t=4\ \text{s}