Question

A constant force of 200N acts on a body for 4 sec for changing its momentum. The change of momentum of
the body in kg
(A) 400
(B) 800
(C) 200
(D) 100​

Answer 1

Answer:

800

Explanation: 200*** 4= 800

Answer 2

Given :

▪ Force acts on the body = 200N

▪ Time interval = 4s

To Find :

▪ Change in momentum of the body.

Concept :

→ This question is completely based on concept of Newton's second law of motion.

→ According to this law,

Applied force = Rate of change in linear momentum

Mathematically,

$\bigstar\:\underline{\boxed{\bf{\red{F\times \Delta t=\Delta P }}}}$

Terms indication :

• F denotes applied force
• Δt denotes time interval
• ΔP denotes change in momentum

Calculation :

$\dashrightarrow\sf\:F\times \Delta t=\Delta P\\ \\ \dashrightarrow\sf\:200\times 4=\Delta P\\ \\ \dashrightarrow\gray{\underline{\boxed{\bf{\orange{\Delta P=800\:Ns}}}}}\:\green{\bigstar}$

Additional Information :

• Force is a polar vector as it has a point of application.
• Momentum is also a vector quantity.
• Vector quantity has both magnitude as well as direction.