English Medium कक्षा १० - CBSE Question Bank Solutions for Science

The figure given below shows an electric circuit in which current flows from a 6 V battery through two resistors. 

1. Are the resistors connected in series with each other or in parallel?
2. For each resistors, state the p.d. across it.
3. The current flowing from the battery is shared between the two resistors. Which resistor will have bigger share of the current?
4. Calculate the effective resistance of the two resistors.
5. Calculate the current that flows from the battery.

(a) With the help of a circuit diagram, obtain the relation for the equivalent resistance of two resistances connected in parallel.
(b) In the circuit diagram shown below, find:

(i) Total resistance.
(ii) Current shown by the ammeter A 

A battery and three lamps are connected as shown: 

Which of the following statements about the currents at X, Y and Z is correct?
(a) The current at Z is greater than that at Y.
(b) The current at Y is greater than that at Z.
(c) The current at X equals the current at Y.
(d) The current at X equals the current at Z. 

V₁, V₂ and V₃ are the p.ds. across the 1Ω, 2Ω and 3Ω resistors in the following diagram, and the current is 5 A.  

Which one of the columns (a) to (d) shows the correct values of V₁, V₂ and V₃measured in volts? 

           `V_1`   `V_2`  `V_3` 

(a)         1.0       2.0        3.0                    

(b)         5.0       10.0      15.0

(c)         5.0       2.5        1.6                 

(d)         4.0       4.0        2.0 

You can given one hundred 1 Ω resistors. What is the smallest and largest resistance you can make in a circuit using these?

If the lamps are both the same in the figure given below and if A₁ reads 0.50 A, what do A₂, A₃, A₄ and A₅ read? 

What happens to the other bulbs in a series circuit if one bulb blows off?

What happens to the other bulbs in a parallel circuit if one bulb blows off?

Which type of circuit, series or parallel, is preferred while connecting a large number of bulbs: 

(a) for decorating a hotel building from outside?

Which type of circuit, series or parallel, is preferred while connecting a large number of bulbs:  

(b) for lighting inside the rooms of the hotel?

Draw a circuit diagram to show how two 4 V electric lamps can be lit brightly from two 2 V cells.

Give three reasons why different electrical appliances in a domestic circuit are connected in parallel.

Ten bulbs are connected in a series circuit to a power supply line. Ten identical bulbs are connected in a parallel circuit to an identical power supply line. 

(a) Which circuit would have the highest voltage across each bulb?

Ten bulbs are connected in a series circuit to a power supply line. Ten identical bulbs are connected in a parallel circuit to an identical power supply line. 

(b) In which circuit, if one bulbs be brighter?

Ten bulbs are connected in a series circuit to a power supply line. Ten identical bulbs are connected in a parallel circuit to an identical power supply line. 

(c) In which circuit, if one bulb blows out, all other will stop glowing?

Ten bulbs are connected in a series circuit to a power supply line. Ten identical bulbs are connected in a parallel circuit to an identical power supply line. 

(d) Which circuit would have less current in it?

Consider the circuit given below: 

(a) In which circuit are the lamps dimmest?
(b) In which circuit or circuits are the lamps of equal brightness to the lamps in circuit (i)?
(c) Which circuit gives out the maximum light?  

If you were going to connect two light bulbs to one battery, would you use a series or a parallel arrangement? Why? Which arrangement takes more current from the battery?

Which is the better way to connect lights and other electrical appliances in domestic wiring: series circuits or parallel circuits? why?

 Christmas tree lamps are usually wired in series. What happens if one lamps breaks?