Q. No.The current-voltage relation of the diode is given by \(I=(e^{1000V/T}-1)~\text{mA}\), where the applied voltage \(V\) is in volts and the temperature \(T\) is in degree Kelvin. If a student makes an error measuring \(\pm ~0.01~\text{V}\) while measuring the current of \(5~\text{mA}\) at \(300~\text{K}\), what will be the error in the value of current in \(\text{mA}\)?
1. \(0.02~\text{mA}\)
2. \(0.5~\text{mA}\)
3. \(0.05~\text{mA}\)
4. \(0.2~\text{mA}\)
A student measured the length of a rod and wrote its as \(3.50~\text{cm}\). Which instrument did he use to measure it?
| 1. | A vernier calliper where the \(10\) divisions in the vernier scale match with \(9\) divisions in the main scale and main scale has \(10\) divisions in \(1~\text{cm}\) |
| 2. | A screw gauge having \(100\) divisions in the circular scale and pitch as \(1~\text{mm}\) |
| 3. | A screw gauge having \(50\) divisions in the circular scale and pitch as \(1~\text{mm}\) |
| 4. | A meter scale |
The period of oscillation on a simple pendulum is \(T=2\pi\sqrt{\frac{L}{g}}\). The measured value of \(L\) is \(20.0~\text{cm}\) known to have \(1~\text{mm}\) accuracy and the time for \(100\) oscillations of the pendulum is found to be \(90~\text{s}\) using a wristwatch of \(1~\text{s}\) resolution. The accuracy in the determination of \(g\) is:
1. \(2\%\)
2. \(3\%\)
3. \(1\%\)
4. \(5\%\)
1. \(u=\frac{e^2 h}{e a_0}\)
2. \(u=\frac{{e}^2 {c}}{h {a}_0}\)
3. \(u=\frac{h c}{e^2 a_0}\)
4. \(u=\frac{e^2a_0}{hc}\)
| S.No | MS \(\text{(cm)}\) | VS divisions |
| 1 | 0.5 | 8 |
| 2 | 0.5 | 4 |
| 3 | 0.5 | 6 |
1. \(0.53~\text{cm}\)
2. \(0.56~\text{cm}\)
3. \(0.59~\text{cm}\)
4. \(0.52~\text{cm}\)
1. \({\left(\frac{h}{m e^2}\right)}\)
2. \({\left(\frac{hc}{m e^2}\right)}\)
3. \({\left(\frac{h}{c e^2}\right)}\)
4. \({\left(\frac{mc^2}{h e^2}\right)}\)
1. \({\eta\left(\frac{S \Delta \theta}{h}\right)\left(\frac{1}{\rho g}\right)}\)
2. \({\eta\left(\frac{S \Delta \theta}{\eta h}\right)\left(\frac{1}{\rho g}\right)}\)
3. \({S\Delta \theta\over \eta h}\)
4. \(\eta{S\Delta \theta\over h}\)
A student measures the time period of \(100\) oscillations of a simple pendulum four times. The data set is \(90~\text{s}, ~91~\text{s},~95~\text{s}~\text{and}~92~\text{s}.\) If the minimum division in the measuring clock is \(1~\text{s}\), then the reported mean time should be:
1. \( 92 \pm 2 ~\text{s} \)
2. \( 92 \pm 5.0 ~\text{s} \)
3. \( 92 \pm 1.8 ~\text{s} \)
4. \( 92 \pm 3~\text{s} \)
A screw gauge with a pitch of \(0.5~\text{mm}\) and a circular scale with \(50\) divisions is used to measure the thickness of a thin sheet of Aluminium. Before starting the measurement, it is found that when the two jaws of the screw gauge are brought in contact, the \(45^{\text{th}}\) division coincides with the main scale line and that the zero of the main scale is barely visible. What is the thickness of the sheet if the main scale reading is \(0.5~\text{mm}\) and the \(25^{\text{th}}\) division coincides with the main scale line?
1. \(0.75~\text{mm}\)
2. \(0.80~\text{mm}\)
3. \(0.70~\text{mm}\)
4. \(0.50~\text{mm}\)
The following observations were taken to determine the surface tension \(T\) of water by the capillary method:
diameter of the capillary, \(D=1.25 \times 10^{-2} ~\text{m}\)
rise of water, \(h=1.45\times 10^{-2}~\text{m}\)
Using \(g= 9.80~\text{m/s}^2\) and the simplified relation, the possible error in surface tension is closest to:
1. \(0.15\%\)
2. \(1.5\%\)
3. \(2.4\%\)
4. \(10\%\)
© 2025 GoodEd Technologies Pvt. Ltd.