The newton second (also newton-second, symbol N s or N·s) is the derived SI unit of impulse. It is dimensionally equivalent to the momentum unit kilogram metre per second (kg·m/s). One newton second corresponds to a one-newton force applied for one second.
|Unit system||SI derived unit|
|Unit of||Impulse and momentum|
|Named after||Isaac Newton|
|In SI base units:||kg ⋅ m/s|
It can be used to identify the resultant velocity of a mass if a force accelerates the mass for a specific time interval.
Momentum is given by the formula:
- is the momentum in newton second (N s) or "kilogram meters per second" (kg·m/s)
- is the mass in kilogram
- is the velocity in meters per second (m/s)
- N s = N s= kg m/s
This table gives the magnitudes of some momenta for various masses and speeds.
|0.42||2.4||1||A 420 gram football (FIFA specified weight for outdoor size 5) kicked to a speed of 8.6 km/h.|
|0.42||38||16||The momentum of the famous football kick of the Brazilian player Roberto Carlos in the match against France in 1997. The football had a speed of 137 km/h, making it one of the hardest kicks measured.|
|1,300||10||13,000||A four-door car weighing 1,300 kg (2,866 lb) crashing at 36 km/h (22.37 mph).|
|2,000||10||20,000||A mid-size SUV weighing 2,000 kg (4,409 lb) crashing at 36 km/h (22.37 mph).|
|6||1||6||The total impulse of a class C model rocket engine, which can be found in amateur fireworks.|
|10||2||20||The total impulse of a class D model rocket engine, which also can be found in amateur fireworks.|
|2,030,000||8050||1.63x1010||Space Shuttle launched from earth to orbit|
|45,702||10834||4.95x108||Apollo 11 launched from earth to orbit|
|0.0075||350||2.6||A 7.5-gram handgun bullet (e.g. 9mm Parabellum) fired at 350 m/s.|
|0.004||945||3.8||A 4-gram assault rifle bullet (e.g. 5.56×45mm NATO) fired at 945 m/s.|
|0.05||860||43||A 50-gram machine gun bullet (e.g. .50 BMG) fired at 860 m/s.|