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The period of a body under SHM is presented by T=PaDbScT = P^a D^b S^c; where PP is pressure, DD is density and SS is surface tension. The value of aa, bb and cc are:

A

-3/2, 1/2, 1

B

-1, -2, 3

C

1/2, -3/2, -1/2

D

1, 2, 1/3

Step-by-Step Solution

We use the method of dimensions to solve for the exponents aa, bb, and cc.

  1. Identify Dimensions: Period (TT): [T][T] Pressure (PP): Force/Area = [ML1T2][ML^{-1}T^{-2}] . Density (DD): Mass/Volume = [ML3][ML^{-3}] . Surface Tension (SS): Force/Length = [MT2][MT^{-2}] .

  2. Equate Dimensions: [T]=[P]a[D]b[S]c[T] = [P]^a [D]^b [S]^c [M0L0T1]=[ML1T2]a[ML3]b[MT2]c[M^0 L^0 T^1] = [ML^{-1}T^{-2}]^a [ML^{-3}]^b [MT^{-2}]^c [M0L0T1]=[Ma+b+cLa3bT2a2c][M^0 L^0 T^1] = [M^{a+b+c} L^{-a-3b} T^{-2a-2c}]

  3. Solve System of Equations: For Mass (MM): a+b+c=0a + b + c = 0 (Eq. 1) For Length (LL): a3b=0a=3b-a - 3b = 0 \Rightarrow a = -3b (Eq. 2)

  • For Time (TT): 2a2c=1-2a - 2c = 1 (Eq. 3)
  1. Calculation: Substitute a=3ba = -3b into Eq. 1: (3b)+b+c=0c=2b(-3b) + b + c = 0 \Rightarrow c = 2b. Substitute a=3ba = -3b and c=2bc = 2b into Eq. 3: 2(3b)2(2b)=1-2(-3b) - 2(2b) = 1 6b4b=12b=1b=1/26b - 4b = 1 \Rightarrow 2b = 1 \Rightarrow b = 1/2 Find aa: a=3(1/2)=3/2a = -3(1/2) = -3/2. Find cc: c=2(1/2)=1c = 2(1/2) = 1.

Therefore, a=3/2,b=1/2,c=1a = -3/2, b = 1/2, c = 1.

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