The energy required to break one bond in DNA is \(10^{-20}~\text{J}\). This value in eV is nearly:
1. \(0.6\)
2. \(0.06\)
3. \(0.006\)
4. \(6\)
Dimensions of stress are:
1. \(
{\left[\mathrm{ML}^2 \mathrm{~T}^{-2}\right]}
\)
2. \( {\left[\mathrm{ML}^0 \mathrm{~T}^{-2}\right]}
\)
3. \( {\left[\mathrm{ML}^{-1} \mathrm{~T}^{-2}\right]}
\)
4. \( {\left[\mathrm{MLT}^{-2}\right]}\)
1. | \(9.98\) m | 2. | \(9.980\) m |
3. | \(9.9\) m | 4. | \(9.9801\) m |
A screw gauge has the least count of \(0.01~\text{mm}\) and there are \(50\) divisions in its circular scale. The pitch of the screw gauge is:
1. | \(0.25\) mm | 2. | \(0.5\) mm |
3. | \(1.0\) mm | 4. | \(0.01\) mm |
The angle of \(1'\) (minute of an arc) in radian is nearly equal to:
1. \(2.91 \times 10^{-4} ~\mathrm{rad} \)
2. \(4.85 \times 10^{-4} ~\mathrm{rad} \)
3. \(4.80 \times 10^{-6} ~\mathrm{rad} \)
4. \(1.75 \times 10^{-2} ~\mathrm{rad}\)
Time intervals measured by a clock give the following readings:
\(1.25\) s, \(1.24\) s, \(1.27\) s, \(1.21\) s and \(1.28\) s.
What is the percentage relative error of the observations?
1. \(2\)%
2. \(4\)%
3. \(16\)%
4. \(1.6\)%
The main scale of a vernier calliper has \(n\) divisions/cm. \(n\) divisions of the vernier scale coincide with \((n-1)\) divisions of the main scale. The least count of the vernier calliper is:
1. \(\dfrac{1}{(n+1)(n-1)}\) cm
2. \(\dfrac{1}{n}\) cm
3. \(\dfrac{1}{n^{2}}\) cm
4. \(\dfrac{1}{(n)(n+1)}\) cm
A screw gauge gives the following reading when used to measure the diameter of a wire.
Main scale reading: 0 mm
Circular scale reading: 52 divisions
Given that 1 mm on main scale corresponds to 100 divisions of the circular scale. The diameter of wire from the above data is:
(1) 0.052 cm
(2) 0.026 cm
(3) 0.005 cm
(4) 0.52 cm
If force \([F]\), acceleration \([A]\) and time \([T]\) are chosen as the fundamental physical quantities, then find the dimensions of energy:
1. \(\left[FAT^{-1}\right]\)
2. \(\left[FA^{-1}T\right]\)
3. \(\left[FAT\right]\)
4. \(\left[FAT^{2}\right]\)
If \(E\) and \(G\), respectively, denote energy and gravitational constant, then \(\dfrac{E}{G}\) has the dimensions of:
1. | \([ML^0T^0]\) | 2. | \([M^2L^{-2}T^{-1}]\) |
3. | \([M^2L^{-1}T^{0}]\) | 4. | \([ML^{-1}T^{-1}]\) |