MP Board · Class 9 · Science · Force and Laws of MotionAn object of mass $5\text{ kg}$ is accelerated uniformly from a velocity of $4\text{ m/s}$ to $12\text{ m/s}$ in $4\text{ s}$. What is the magnitude of the force applied on the object?

Correct Option: B ($10\text{ N}$)

Step-by-step Solution:

1. Given Data:

   • Mass of the object ($m$) = $5\text{ kg}$
   • Initial velocity ($u$) = $4\text{ m/s}$
   • Final velocity ($v$) = $12\text{ m/s}$
   • Time taken ($t$) = $4\text{ s}$

2. Calculate Acceleration ($a$): Using the formula for acceleration: $$a = \frac{v - u}{t}$$ $$a = \frac{12 - 4}{4} = \frac{8}{4} = 2\text{ m/s}^2$$

3. Calculate Force ($F$): According to Newton's Second Law of Motion: $$F = m \times a$$ $$F = 5\text{ kg} \times 2\text{ m/s}^2 = 10\text{ N}$$ \nTherefore, the magnitude of the applied force is $10\text{ N}$.