WBJEE · Physics · Current Electricity
A battery of emf \(\mathrm{E}\) and internal resistance \(\mathrm{r}\) is connected with an external resistance \(\mathrm{R}\) as shown in the figure. The battery will act as a constant voltage source if
- A \(r< < R\)
- B \(r>>R\)
- C \(r=R\)
- D It will never act as a constant voltage source
Answer & Solution
Correct Answer
(A) \(r< < R\)
Step-by-step Solution
Detailed explanation
\(V_R=\frac{E}{(R+r)} \times R, \quad V_R=\frac{E}{(1+r / R)}\) \(r < R, V_R \approx E\)
See the Complete Solution
Get step-by-step explanations for this and 2.5 Lakh+ more JEE, NEET & CET questions.
- Unlock all solutions
- Practice the full chapter
- Track accuracy across PYQs
4.8 rated on Google Play · 14,000+ reviews
More questions from Physics
- What will be current through the \(200 \Omega\)
resistor in the given circuit, a long time after the switch \(K\) is made on?
WBJEE 2018 Medium - A rectangular coil carrying-current is placed in a non-uniform magnetic field. On that coil, the totalWBJEE 2016 Easy
- A non-zero current passes through the galvanometer \(G\) shown in the circuit when the key \(K\) is closed and its value does not change when the key is opened. Then, which of the following statement(s) is/are true?
WBJEE 2018 Hard - The value of ' \(\lambda\) ' for which the two vectors \(\vec{a}=5 \hat{i}+\lambda \hat{j}+\hat{k}\) and \(\vec{b}=\hat{i}-2 \hat{j}+\hat{k}\) are perpendicular to each other isWBJEE 2010 Easy
- The distance between an object and a divergent lens is \(\mathrm{m}\) times the focal length of the lens. The linear magnification produced by the lens isWBJEE 2009 Medium
- The minimum wavelength of Lyman series lines is \(P\), then the maximum wavelength of these lines isWBJEE 2025 Medium
More PYQs from WBJEE
- If \(f(x)\) is a function such that \(f^{\prime}(x)=(x-1)^{2}(4-x),\) thenWBJEE 2016 Medium
- If \(\log _7 2=\lambda\), then the value of \(\log _{49}(28)\) isWBJEE 2011 Easy
- In the circuit shown below, the switch is kept in position \(a\) for a long time and is then thrown to position \(b .\) The amplitude of the resulting oscillating current is given by
WBJEE 2015 Medium - A coin is tossed again and again. If tail appears on first three tosses, then the chance that head appears on fourth toss isWBJEE 2011 Easy
- A point is in motion along a hyperbola \(y=\frac{10}{x}\) so that its abscissa \(x\) increases uniformly at a rate of 1 unit per second. Then, the rate of change of its ordinate when the point passes through (5,2)WBJEE 2019 Easy
- Which of the following statements is correct for a spontaneous polymerization reaction ?WBJEE 2024 Easy