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# Electricity

10th Class - CBSE - Physics - 2531 Questions - 0 Concepts

#### Important Questions

Q1 Single Correct Medium
Current-voltage characteristics of two elements $A$ and $B$ are shown in figure (i) and (ii) respectively.
Which of the following graphs represents current-voltage characteristics for their series combination?
• A.
• B.
• C.
• D.

1 Verified Answer | Published on 07th 09, 2020

Q2 Single Correct Medium
A letter 'A' is constructed of a uniform wire of resistance $1 ohm/cm$. The sides of the letter are $20 cm$ long and the cross piece in the middle is $10 cm$ long while the vertex angle is $60^{o}$. The resistance of the letter between the two ends of the legs is:
• A. $\dfrac{40}{3}\Omega$
• B. $40 \Omega$
• C. $10 \Omega$
• D. $\dfrac{80}{3}\Omega$

1 Verified Answer | Published on 07th 09, 2020

Q3 Single Correct Medium
Appliances based on heating effect of current work on
• A. only A.C.
• B. only D.C.
• C. both A.C. and D.C.
• D. none of these

1 Verified Answer | Published on 07th 09, 2020

Q4 Single Correct Medium
Using three wires of resistances 1 ohm, 2ohm and 3 ohm, number of different possible values of resistances are:

• A.  6
• B.  4
• C.  10
• D.  8

1 Verified Answer | Published on 07th 09, 2020

Q5 Single Correct Hard
A material $B$ has twice the specific resistance of $A$. A circular wire made of $B$ has twice the diameter of a wire made of $A$. Then for the two wires to have the same resistance, the ratio $l_{B}$ / $l_{A}$ of their respective lengths must be:
• A. 1
• B. 1/2
• C. 1/4
• D. 2

1 Verified Answer | Published on 07th 09, 2020

Q6 Subjective Hard
In the circuit shown all five resistors have the same value $200\ \Omega$ and each cell has an emf $3\ volts.$ Find the open circuit voltage and the short circuit current for the terminals $A$ and $B.$

1 Verified Answer | Published on 07th 09, 2020

Q7 Single Correct Hard
Three charges, each +q, are placed at the corners of an isosceles triangle ABC of sides BC and AC=2a. D and E are the midpoints of BC and CA, as shown in the figure. The work done in taking a charge Q from D to E is
• A. $\dfrac { qQ }{ 8\pi { \varepsilon }_{ 0 }a }$
• B. $\dfrac { qQ }{ 4\pi { \varepsilon }_{ 0 }a }$
• C. $\dfrac { 3qQ }{ 4\pi { \varepsilon }_{ 0 }a }$
• D. zero

1 Verified Answer | Published on 07th 09, 2020

Q8 Single Correct Hard
The arc AB with the centre C and the infinitely long wire having linear charge density $\lambda$ are lying in the same plane. The minimum amount of work to be done to move a point charge ${q_0}$ from point A to B through a circular path AB of radius $a$ is equal to:
• A. $\dfrac{{q_0^2}}{{2\pi {\varepsilon _0}}}\log \left( {\dfrac{2}{3}} \right)$
• B. $\dfrac{{{q_0}\lambda }}{{2\pi {\varepsilon _0}}}\log \left( {\dfrac{2}{3}} \right)$
• C. $\dfrac{{{q_0}\lambda }}{{\sqrt 2 \pi {\varepsilon _0}}}$
• D. $\dfrac{{{q_0}\lambda }}{{2\pi {\varepsilon _0}}}\log \left( {\dfrac{3}{2}} \right)$

1 Verified Answer | Published on 07th 09, 2020

Q9 Single Correct Hard
Two resistance $R_1 = 100 \pm 3 \omega$ and $R_2 = 200 \pm 4\omega$ are connected in series. Find the equivalent resistance of the series combination.
• A. $300 \pm 8$ omega
• B. $600 \pm 7$ omega
• C. $300 \pm 6$ omega
• D. $300 \pm 7$ omega

1 Verified Answer | Published on 07th 09, 2020

Q10 Single Correct Medium
A wire of resistance $20\Omega$ is bent in the form of a square. The resistance between the ends of diagonal is:

• A. $10\Omega$
• B. $20\Omega$
• C. $15\Omega$
• D. $5\Omega$