The frequency of vibration \(f\) of a mass \(m\) suspended from a spring of spring constant \(k\) is given by a relation of type \(f= Cm^{x}k^{y}\); where \(C\) is a dimensionless quantity. The values of \(x\) and \(y\) will be:
1. \(x=\frac{1}{2},~y= \frac{1}{2}\)
2. \(x=-\frac{1}{2},~y= -\frac{1}{2}\)
3. \(x=\frac{1}{2},~y= -\frac{1}{2}\)
4. \(x=-\frac{1}{2},~y= \frac{1}{2}\)

Subtopic: Β Dimensions |
Β 68%
Level 2: 60%+
PMT - 1990
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The quantities \(A\) and \(B\) are related by the relation, \(m= \frac{A}{B}\), where \(m\) is the linear density and \(A\) is the force. The dimensions of \(B\) are of:

1. Pressure 2. Work
3. Latent heat 4. None of the above
Subtopic: Β Dimensions |
Level 3: 35%-60%
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The velocity of water waves \(𝑣\) may depend upon their wavelength \(πœ†\), the density of water \(𝜌\) and the acceleration due to gravity \(g\). The method of dimensions gives the relation between these quantities as:
1. \(v^2 \propto g\lambda^{-1}\rho^{-1}\)
2. \(v^2 \propto g\lambda\rho\)
3. \(v^2 \propto g\lambda\)
4. \(v^2 \propto g^{-1}\lambda^{-3}\)

Subtopic: Β Dimensions |
Β 71%
Level 2: 60%+
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The equation of a wave is given by Y=Asinω(xv−k) where ω is the angular velocity, x is length and v is the linear velocity. The dimension of k is 

(1) LT

(2) T

(3) T−1

(4) T2

Subtopic: Β Dimensions |
Β 75%
Level 2: 60%+
PMT - 1993
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The period of a body under SHM i.e. presented by T=PaDbSc; where P is pressure, D is density and S is surface tension. The value of a, b and c are 

(1) −32, 12, 1

(2) −1, −2, 3

(3) 12, −32, −12

(4) 1, 2, 13

Subtopic: Β Dimensions |
Β 64%
Level 2: 60%+
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The velocity of a freely falling body changes as gphq where g is acceleration due to gravity and h is the height. The values of p and q are 

(1) 1,12

(2) 12,12

(3) 12, 1

(4) 1, 1

Subtopic: Β Dimensions |
Β 86%
Level 1: 80%+
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A small steel ball of radius \(r\) is allowed to fall under gravity through a column of a viscous liquid of coefficient of viscosity \(\eta\). After some time the velocity of the ball attains a constant value known as terminal velocity \(v_T\). The terminal velocity depends on \((\text{i})\) the mass of the ball \(m\) \((\text{ii})\) \(\eta\) \((\text{iii})\) \(r\) and \((\text{iv})\) acceleration due to gravity \(g\). Which of the following relations is dimensionally correct:

1. \(v_T \propto \frac{mg}{\eta r}\) 2. \(v_T \propto \frac{\eta r}{mg}\)
3. \(v_T \propto \eta rmg\) 4. \(v_T \propto \frac{mgr}{\eta }\)
Subtopic: Β Dimensions |
Β 63%
Level 2: 60%+
PMT - 1992
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The quantity X=ε0LVt:ε0 is the permittivity of free space, L is length, V is the potential difference and t is time. The dimensions of X are the same as that of  

(1) Resistance

(2) Charge

(3) Voltage

(4) Current

Subtopic: Β Dimensions |
Β 57%
Level 3: 35%-60%
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The dimensions of physical quantity X in the equation Force =XDensity is given by 

(1) M1L4T−2

(2) M2L−2T−1

(3) M2L−2T−2

(4) M1L−2T−1

Subtopic: Β Dimensions |
Β 84%
Level 1: 80%+
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Two quantities A and B have different dimensions. Which mathematical operation given below is physically meaningful 

(1) A/B

(2) A + B

(3) A – B

(4) None

Subtopic: Β Dimensions |
Β 81%
Level 1: 80%+
PMT - 1997
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