The area of a square is \(5.29~\text{cm}^2. \) The area of \(7\) such squares taking into account the significant figures is:
1. \(37.03~\text{cm}^2\)
2. \(37.0~\text{cm}^2\)
3. \(37~\text{cm}^2\)
4. \(37.030~\text{cm}^2\)

Subtopic:  Significant Figures |
Level 3: 35%-60%
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The least count of the main scale of a vernier callipers is \(1~\mathrm{mm}\). Its vernier scale is divided into \(10\) divisions and coincide with \(9\) divisions of the main scale. When jaws are touching each other, the \(7^{th}\) division of vernier scale coincides with a division of main scale and the zero of vernier scale is lying right side of the zero of main scale. When this vernier is used to measure length of a cylinder the zero of the vernier scale between \(3.1~\mathrm{cm}\) and \(3.2~\mathrm{cm}\) and \(4^{th}\) VSD coincides with a main scale division. The length of the cylinder is : (VSD is vernier scale division)
1. \(3.21~\text{cm}\)
2. \(2.99 ~\text{cm}\) 
3. \(3.2~\text{cm}\)
4. \(3.07~\text{cm}\)

Subtopic:  Measurement & Measuring Devices |
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Level 3: 35%-60%
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If speed \(v\), area \(A\) and force \(F\) are chosen as fundamental units, then the dimension of Young's modulus will be:
1. \(\left[FA^{-1} v^0 \right]\)
2. \(\left[FA^2 v^{-1} \right]\)
3. \( \left[FA^2 {v}^{-3}\right]\)
4. \(\left[FA^2 v^{-2}\right] \)

Subtopic:  Dimensions |
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Level 2: 60%+
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If momentum \((P), \) area \((A) ,\) and time \((T)\) are taken as the fundamental physical quantities, then the dimensional formula of energy in terms of \(P,\) \(A,\) and \(T\) is:

1. \(\left [PA^{-1}T^{-2} \right ] \) 2. \(\left [PA^{1/2}T^{-1} \right ] \)
3. \(\left [P^2AT^{-2} \right ] \) 4. \(\left [P^{1/2}AT^{-1} \right ] \)
Subtopic:  Dimensions |
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Level 1: 80%+
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Using a screw gauge with pitch \(0.1 ~\text{cm}\) and \(50\) divisions on its circular scale, the thickness of an object is measured. It should be accurately recorded as:
1. \(2.124~\text{cm}\)
2. \(2.121~\text{cm}\)
3. \(2.125~\text{cm}\)
4. \(2.123~\text{cm}\)

Subtopic:  Measurement & Measuring Devices |
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Level 3: 35%-60%
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The amount of solar energy received on the earth’s surface per unit area per unit time is defined as a solar constant. Dimension of solar constant is:
1. \(\left[ M L^2 T^{-2}\right]\)
2. \(\left[M^2 L^0 T^{-1}\right] \)
3. \( \left[ML T^{-2}\right] \)
4. \( \left[M L^0 T^{-3}\right]\)

Subtopic:  Dimensions |
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Level 2: 60%+
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A physical quantity \(z\) depends on four observables \(a,b,c\) and \(d\), as \(z=\frac{a^2 b^{\frac{2}{3}}}{\sqrt{c }d^3}\) The percentage of error in the measurement of \(a,b,c\) and \(d\) is  \(2\%\), \(1.5\%\), \(4\%\) and \(2.5\%\) respectively. The percentage of error in \(z\) is:
1. \(12.25\%\)
2. \(14.5\%\)
3. \(16.5\%\)
4. \(13.5\%\)

Subtopic:  Errors |
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Level 1: 80%+
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The quantities \(x=\frac{1}{\sqrt{\mu_0 \varepsilon_0}}, y=\frac{E}{B} \) and \(z=\frac{L}{C R}\) are defined where \(C\)-capacitance, \(R\)-Resistance, \(L\)-length, \(E\)-Electric field, \(B\)-magnetic field and \(\varepsilon_0, \mu_0\) free space permittivity and permeability respectively. Then:

1. Only \(x\) and \(y\) have the same dimension
2. \(x\), \(y\) and \(z\) have the same dimension
3. Only \(x\) and \(z\) have the same dimension
4. Only \(y\) and \(z\) have the same dimension

Subtopic:  Dimensions |
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The dimensional formula for thermal conductivity is: (here \(K\) denotes the temperature)
1. \( \left[M L T^{-2} K\right] \)
2. \( \left[M L T^{-3} K\right] \)
3. \( \left[M L T^{-3} K^{-1}\right] \)
4. \( \left[M L T^{-2} K^{-2}\right]\)

Subtopic:  Dimensions |
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Level 2: 60%+
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A quantity \(x\) is given by \(\left(\frac{IFv^2}{WL^4}\right) \) in terms of moment of inertia \(I\), force \(F\), velocity \(v\), work \(W\), and Length \(L\). The dimensional formula for \(x\) is the same as that of:

1. Coefficient of viscosity
2. Planck's constant
3. Energy density
4. Force constant

Subtopic:  Dimensions |
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Level 2: 60%+
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