Question

Shown below is a velocity-time graph for an object of mass 50 kg 1s the force acting on the objeet

constant magnitude. Caleulate the magnitude of the foree.​

Answer 1

see, first we should understand, what is the area of force-time graphs shows. It's the impulse. And impulse is equals to change in momentum.

first find impulse,

impluse = area

            =((1/2)×2×10)+ (2×10)+ ((1/2)×(10+20)×2)+((1/2)×4×20)

            =10+20+30+40

            =100 N-s

now, impulse = change in momentum

                     =m×v - m×u

where v= final velocity and u =initial velocity =0

so, 100 = 2×v  

⇒v = 50 m/s

hope this will help you