Momentum

Momentum

how much motion you carry

Momentum is mass times velocity; a heavier or faster object carries more, and because velocity has a direction, so does momentum.

Example

Momentum is mass times velocity — a heavier or faster object carries more, and because velocity has a direction, so does momentum.

highlighted = computed this step

Momentum is mass times velocity

Momentum measures how much motion something carries: its mass times its velocity. A heavier cart or a faster cart has more. Because velocity has a direction, so does momentum.

p=m vp = m\,v
A moving cart carries momentumA cart on a track with a velocity arrow pointing in its direction of motion.mv

A worked value

A 2 kilogram cart rolling at 3 metres per second carries 2 times 3, or 6 kilogram metres per second of momentum, to the right. The same cart rolling the other way, left at 3 metres per second, would carry the opposite sign, minus 6 kilogram metres per second.

p=m v=2 kg ⋅ 3 m/s=6 kg m/sp = m\,v = 2\ \text{kg} \,\cdot\, 3\ \text{m}/\text{s} = \hl{6}\ \text{kg}\,\text{m}/\text{s}
mechanics A 2 kg cart at 3 m/s gives a clean 6 kg m/s of momentum.