Question

Momentum of a body increase from 20 kg m/s to 40 kg m/s then the force applied is

Answer 1

Answer:

force is 20 newton

Explanation:

force is equal to rate of change of momentum so

F = 40 - 20 = 20 N

Answer 2

Given:-

• initial momentum = 20 kgm/s
• final momentum = 40 kgm/s
• time = 5 seconds

To find:-

• Force applied to this body

Formula:-

$\underline\red{\boxed{\bf Force = \dfrac{mv-mu}{t}}}$

here, mv = final momentum

• mu = initial momentum
• t = time

Solution:-

→ $\sf F = \dfrac{40-20}{5}$

→ $\sf F = \dfrac{20}{5}$

→ $\sf F = 4 N$

hence, the required answer is 4 N i.e (a) option

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Momentum:-

• the momentum of an object is equal to the mass of the object times the velocity of the object.
• momentum = mass × velocity
• rate of change in momentum leads to force which is :-

$\underline\red{\boxed{\bf Force = \dfrac{final\:momentum(mv)-initial\:momentum(mu)}{time(t)}}}$

• it's SI unit is kgm/s

ALWAYS KEEP AN EYE OVER THE UNITS