question_answer

The force F acting on a particle of mass m is indicated by the force-time graph shown below. The change in momentum of the particle over the time interval from zero to 8 s is

A) 24 N s             

B)        20 N s 

C)        12 N s             

D)        6 N s   

Correct Answer: C

Solution :

Change in momentum = Area under F-t graph in that interval = Area of \[\Delta ABC-\] Area of rectangle CDEF + Area of rectangle FGHI \[=\frac{1}{2}\times 2\times 6-3\times 2+4\times 3=12Ns\]