Electricity Class 10 Worksheet Science Chapter 11

Objective Type Questions

Q1: Two resistors of resistances 2 Ω and 4 Ω when connected to a battery will have
(a) Same current flowing through them when connected in parallel
(b) Same current flowing through them when connected in series
(c) Same potential difference across them when connected in series
(d) None of these

Q2: The resistance of an electric iron drawing a current of 4A when connected to a 220V mains would be
(a) 1000 Ω
(b) 55 Ω
(c) 44 Ω
(d) 64 Ω

Q3: If 25 joule of work is done in moving a charge of 5C across two points A and B the potential difference between these points would be
(a) V
(b) 125V
(c) 5V
(d) 625V

Q4: Ohm’s law states the relationship between
(a) Electric current and heat produced in it
(b) Electric power and work done
(c) Electric current and potential difference
(d) Electric current and electric charge

Q5: If electrons flow from A to B, current will flow from
(a) A to B
(b) B to A
(c) It will not flow
(d) None of these

Q6: Unit of electric power may also be expressed as
(a) Volt ampere
(b) Kilowatt hour
(c) Watt second
(d) Joule second

Q7: Electric current flows from ‘A’ to ‘B’ in metallic conductor. The point is at higher potential is
(a) A
(b) B
(c) Both have equal potential
(d) Both have lower potential

Q8: When a 4V battery is connected across an unknown resistor there is a current of 100 mA in the circuit.
The value of the resistance of the resister is:
(a) 4 Ω
(b) 40 Ω
(c) 400 Ω
(d) 0.4 Ω

Q9: In an electric circuit three incandescent bulbs of rating 40W, 60W and 100W respectively are connected in parallel to an electric source. Which of the following is likely to happen regarding their brightness
(a) Brightness of all the bulbs will be the same
(b) Brightness of bulb A will be the maximum
(c) Brightness of bulb B will be more than that of A
(d) Brightness of bulb C will be less than that of B

Q10: Electrical resistivity of a given metallic wire depends upon
(a) its length
(b) its thickness
(c) its shape
(d) nature of the material

Fill in the Blanks

Q1: The SI unit of electric potential difference is ___________.

Q2: George Simon Ohm established the relationship between current (I) and potential difference (V) using the formula V = __________.

Q3: The heating effect of electric current is utilized in devices like electric iron, electric toasters, and electric __________.

Q4: In a parallel arrangement of resistances, the total current is the sum of the currents flowing through different resistances, and the sum of the reciprocals of the separate resistances is equal to the reciprocal of the equivalent resistance, given by __________.

Q5: The practical unit of electric energy is a ____________, where 1 kW h = 3.6 x 10⁶ J.

Match the Column (In a Table):

Q1:
 

Assertion and Reasoning Questions

Q1: The following questions consists of two statements –Assertion(A) and Reason (R). Answer these questions selecting the appropriate option given below.
Assertion (A): If a graph is plotted between potential difference and current the graph is a straight line passing through the origin.
Reason(R): current is directly proportional to the potential difference.
(a) Both A and R are true and R is the correct explanation for A
(b) Both A and R are true and R is not the correct explanation for A
(c) A is true but R is false
(d) A is false but R is true.

Q2: The following questions consists of two statements –Assertion(A) and Reason (R). Answer these questions selecting the appropriate option given below.
Assertion (A): Longer wires have greater resistance and the smaller wires have lesser resistance.
Reason(R): Resistance is inversely proportional to the length of the wire.
(a) Both A and R are true and R is the correct explanation for A
(b) Both A and R are true and R is not the correct explanation for A
(c) A is true but R is false
(d) A is false but R is true.

Q3: The following questions consists of two statements –Assertion(A) and Reason (R). Answer these questions selecting the appropriate option given below.
Assertion (A): A cell converts chemical energy into electrical energy.
Reason(R): A cell maintains a potential difference across its terminals due to chemical reactions.
(a) Both A and R are true and R is the correct explanation for A
(b) Both A and R are true and R is not the correct explanation for A
(c) A is true but R is false
(d) A is false but R is true.

Q4: The following questions consists of two statements –Assertion(A) and Reason (R). Answer these questions selecting the appropriate option given below.
Assertion (A): Alloys are commonly used in electrical heating devices.
Reason(R): Alloys do not oxidize at high temperatures.
(a) Both A and R are true and R is the correct explanation for A
(b) Both A and R are true and R is not the correct explanation for A
(c) A is true but R is false
(d) A is false but R is true.

Q5: The following questions consists of two statements –Assertion((a) and Reason (R). Answer these questions selecting the appropriate option given below.
Assertion (A): When resistances are connected between the same two points they are said to be in series.
Reason(R): When resistors are connected in series the current through each resistor is the same.
(a) Both A and R are true and R is the correct explanation for A
(b) Both A and R are true and R is not the correct explanation for A
(c) A is true but R is false
(d) A is false but R is true.

Very Short Answers

Q1: Define resistance. Give its S.I. unit.

Q2: What will happen to the resistivity of a wire of length L if it is cut into three parts?

Q3: The potential difference across the wire having fixed resistance is tripled. By how much does the electric power increase?

Q4: Is electric potential a scalar or a vector quantity ?

Q5: What causes the potential difference between the two terminals of a cell?

Q6: Define 1 Coulomb.

Q7: Calculate the number of electrons in 5C charge?

Q8: What is a good conductor?

Q9: Is human body an insulator or conductor?

Short Answers Type Questions

Q1:  Find the minimum rating of fuse that can be safely used on a line on which two 1.1 KW electric geysers are to run simultaneously.
The supply voltage is 220 V.

Q2: The electric power consumed by a device may be calculated by either of the two expressions P = I2R or P = V2/R. The frist expression indicates that it is directly proportional to R whereas the second expression indicates inverse proportionality. How can the seemingly different dependence of P on R in these expressions be explained?

Q3: Why does the cord of an electric heater does not glow while heating element does?

Q4: How will the heat produced in a resistor R change if its resistance is reduced to half of its initial value, other parameters of the circuit remain unchanged?

Q5: Why is parallel arrangement used in domestic wiring? 

Q6: (A) What is the resistance of a conductor?
(B) What happens to the electrical resistance when mercury is cooled to 4.12 k?
(C) What name is given to this phenomenon?

Q7: Draw a circuit diagram having the following components:
(a) Bulb
(b) A two cell battery
(c) Ammeter
(d) A closed key

Long Answers Type Questions

Q1: Answer the following:
(A) Why ammeter is always connected in series?
(B) give dry cells each of 1.0 volt have internal resistance of 0.2, 0.3, 0.4, 0.5 and 1.2 ohms. When connected in series, what current will these five cells furnish through 10 ohm resistance?

Q2: For the circuit shown in the given diagram:

What is the value of
i. current through 6 resistor?
ii. potential difference across 12 resistor?

Q3: List two distinguishing features between the resistance and resistivity of a conductor. A wire is stretched so that its length becomes 6/5 times of its original length. If its original resistance is 25 W, find its new resistance and resistivity. Give justification for your answer in each case.

Q4: (i) Write an expression for the resistivity of a substance.
(ii) State the SI unit of resistivity.
(iii) Distinguish between resistance and resistivity.
(iv) Name two factors on which the resistivity of a substance depends and two factors on which it does not depend.

Q5: The potential difference between the terminals of an electric heater is 60 V when it draws a current of 4 A from the source. What current will the heater draw if the potential difference is increased upto 120 V?

Q6: State Ohm’s law. Draw a labelled circuit diagram to verify this law in the laboratory. If you draw a graph between the potential difference and current flowing through a metallic conductor, what kind of curve will you get? Explain how would you use this graph to determine the resistance of the conductor.

You can access the solutions to this worksheet here.