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Grade 12th passGeneral Physics

An aitihasik starts from rest and reaches a speed of 54km/hr in 15 seconds the acceleration increases uniformly for first 9 seconds after this the acceleration reduces to zero uniformly in next 6 seconds . Find displacement in 15 second interval

Profile image of Ashu
8 Years agoGrade 12th pass
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1 Answer

Profile image of Saurabh Koranglekar
6 Years ago
Dear student

a1 be acc for first 9 sec

a2 be acc for next 6 sec

now
s9 = 0.5(at^2)
= 40.5*a1

similarly,
s15-s9
s = ut +0.5at^2

u here is (a1*9);
t=6;
and a is a2;

thus forming and simplifying equations answer can be obtained

also 54 kmph is 15 m/s

Regards