The acceleration of a cart started at t = 0, varies with time as shown in figure (3-E2). Find the distance travelled in

30 seconds and draw the position-time graph.


Let u be the initial velocity, v be the final velocity


In the first 10 s,


Distance travelled,




At t= 10 s


v=u + at = 0+5×10 = 50 ft


From 10s to 20s, the particle moves with a uniform velocity of 50 ft/s


Distance covered from t=10 s to t=20 s,


S2 = vt = 50×10 = 500 ft


Acceleration is constant between 20s and 30s.i.e -5 ft/m2


At 20 s velocity is 50 ft/s


t=30-20=10 s


Distance,



Total distance travelled in 30 s is,



Position –time graph



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