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The formula S=u+a(n-1/2) is dimensionally not correct.

But still we use it in variety of applications. Why do we still get the correct answer?

Please reply!!!

6 years ago


Answers : (4)


Sn=un+an^2/2  ...........1               (displacement in n seconds)

Sn-1=u(n-1) +a(n-1)^2 /2.........2   (displacement in n-1 seconds)


     Snth  =u + a(n-1/2) ..............3

in eq 1 , dimension of n is time and in eq 2 ,n-1 second that means 1 in n-1 second is having dimension of time......

1sec is a constant but it is having dimension in same manner in eq 3 ,n-1/2 has dimension of time .....

so this relation is correct

approve my ans if u like

6 years ago

he you have taken this q frm dc pandey na

6 years ago
a particle covers 10m in first 5s and 10m in next 3s. assuming constant acceleration find intial speed, acceleration , distance covered in next 2s.
2 years ago
it is dimentionally correct.
S in nth second in the sense u r talking about the diplacement in that second which will basically have the dimentional formula [M^0*L^1*T^-1]
the rhs also has the same dimentional formula.
2 years ago

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