KVPY2011PhysicsMotion in One Dimension
A body of 0.5 ~kg moves along the positive x -axis under the influence of a varying force F (in Newtons) as shown below. If the speed of the object at x=4 ~m in 3.16 ~ms ⁻¹ then its speed at x=8 ~m is
Options
- A3.16 ~ms ⁻¹
- B9.3 ~ms ⁻¹
- C8 ~ms ⁻¹
- D6.8 ~ms ⁻¹
Correct answer
D. 6.8 ~ms ⁻¹
Step-by-step solution
According to work-energy principle array l W _ C + W _ nc + W _ ext = KE ₄⁸ Fdx = 1 2 mv _ f ²- 1 2 mv _ i ² array 1 2 3 8- 1 2 1.5 4= 1 2 1 2 [v_ f ²-(3.16)² ]v_ f =6.8 ~m / s