Newton second

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newton second
Impuls Masse Geschwindigkeit.svg
For two objects moving with the same velocity (v), the object with the greater mass (m) will have the greater momentum (p).
Unit information
Unit system SI derived unit
Unit of Impulse and momentum
Symbol Ns 
Named after Isaac Newton
In SI base units: kgm/s

The newton second (also newton-second, symbol Ns or N·s)[1] 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.

It can be used to identify the resultant velocity of a mass if a force accelerates the mass for a specific time interval.

Definition[edit]

Momentum is given by the formula:

Examples[edit]

Below, the magnitudes of some momenta are given for various masses and speeds (magnitudes of velocity).

Mass
(kg)
Speed
(m/s)
Momentum
newton seconds
Explanation
0.1 10 1 A 100 gram tomato dropped at a height of 1m on the earth (gravitational acceleration of 9,82  m/s2 gives approx. 1 second flight time).
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.
1,500 16.7 25,050 A regular small car weighing 1.5 tons crashing at 60 km/h
2,600 16.7 43,420 An SUV weighing 2.6 tons crashing at 60 km/h
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 9x19 mm 7.5 gram pistol round launched at 350 m/s
0.004 945 3.8 5.56 mm (.223) 4 gram rifle round launched at 945 m/s
0.05 860 43 12.7x99 mm (.50 BMG) 50 gram rifle round launched at 860 m/s

See also[edit]

References[edit]

  1. ^ International Bureau of Weights and Measures (2006), The International System of Units (SI) (PDF) (8th ed.), ISBN 92-822-2213-6