Question
On increasing the current drawn from a cell, the net potential difference across its terminals is lowered, why?
✓
Answer
The terminal potential difference V = E - Ir.
Clearly if I is increased, the terminal potential difference falls.
Clearly if I is increased, the terminal potential difference falls.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
You are given a low resistance $R_1$, a high resistance $R_2$ and a galvanometer. How will you make such instruments from them which can measure (i) current, (ii) potential difference?
→Magnetic flux passing through plane of any coil is changing with time according to the relation $\phi=$ $\left(5 t^3+4 t^2+2 t-5\right) Wb$. Find the induced current in the coil at $t=2$ seconds given that resistance of the coil is 5 ohms.
→Write the formula to find the Rydberg's constant and what is the value of their constant?
The angle made by the string of a simple pendulum with the vertical depends on time as $\theta=\frac{\pi}{90}\sin[(\pi\text{s}^{-1})\text{t}].$ Find the length of the pendulum if $\text{g}=\pi^2\text{m/s}^2.$
→If a constant potential difference is applied across a bulb, the current slightly decreases as time passes and then becomes constant. Explain.
White light is used in a Young's double slit experiment. Find the minimum order of the violet fringe $(\lambda=400\text{nm}),$ which overlaps with a red fringe $(\lambda=700\text{nm}).$
→Evaluate Rydberg constant by putting the values of the fundamental constants in its expression.
A current of 10A is established in a long wire along the positive z-axis. Find the magnetic field $\overrightarrow{\text{B}}$ at the point (1m, 0, 0).
→In the upper wire is made of steel and the lower of copper. The wires have equal cross-section. Find the ratio of the longitudinal strains developed in the two wires.
A molecule of a substance has a permanent electric dipole moment of magnitude $10^{-29} C m$. A mole of this substance is polarised (at low temperature) by applying a strong electrostatic field of magnitude $10^6 V m ^{-1}$. The direction of the field is suddenly changed by an angle of $60^{\circ}$. Estimate the heat released by the substance in aligning its dipoles along the new direction of the field. For simplicity, assume $100 \%$ polarisation of the sample.
→