Class 10 Science Chapter 12 MCQ Online Test for 2020-2021
Class: 10 | Science |
Chapter: 12 | Electricity |
Contents: | MCQ Online Tests with Answers and Explanation |
Class 10 Science Chapter 12 MCQ with Answers for 2020-21
Class 10 Science Chapter 12 MCQ Online Test with solutions and answers. There are more than 70 questions in the form of MCQs covering the entire chapter 12 of Class 10 Science. Most of the questions are confined to Latest NCERT Books for class 10 Science issued for session 2020-2021.
Q1
Which of the following statement is or are incorrect?
[A]. All the matter contains positively charged particles called protons.
[B]. All the metal contains negatively charged particles called electrons
[C]. It is obvious that the unit of electric charge, called column, is much bigger than the charge of a proton or an electron.
[D]. The SI unit of electric charge coulomb is equivalent to the charge contained in 6.35 x 10 to the power 18
Answer: Option D
Explanation:The SI unit of electric charge coulomb is equivalent to the charge contained in 6.25 x 10 to the power 18.
Q2
Deepak appeared in class test but he confused to know the correct statement. Would you help him to know that?
[A]. The potential difference is measured by means of an instrument called voltmeter.
[B]. The potential difference between two points is said to be one volt if one joule of work is done in moving one coulomb of electric charge from one point to the other.
[C]. The SI unit of potential difference is volt.
[D]. All the above.
Answer: Option D
Explanation:Here, all these statements are correct. Hence, your answer will be option [D].
Q3
In an electrical circuit three incandescent bulbs A, B and C of rating 40 W, 60 W and 100 W 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
Answer: Option C
Explanation:In an electrical circuit, three incandescent bulbs A, B and C of rating 40 W, 60 W, and 100 W are connected in parallel to and electrical source, then the bulb with the highest wattage glows with maximum brightness. Thus, the brightness of bulb B (100 W) is maximum.
This brightness different bulks are in following order:
B100 > B60 > B40
Q4
A cylindrical conductor of length l and uniform area of cross section A has resistance R. Another conductor of length 2l and resistance R of the same material has area of cross section
[A]. A/2
[B]. 3A/2
[C]. 2A
[D]. 3A
Answer: Option C
Explanation: In first case,
Resistivity of the conductor, ƿ = RA¹/ l
In second case,
Resistivity of the conductor, ƿ = RA¹/ 2l
Therefore, for same material, resistivity of the conductor will be same.
So, on substituting the value of ƿ in Eq. (ii), we have
RA/I = RA¹/2I = A¹ =2A
Q5
In a science quiz competition, Neha are asked a question where she had to choose the statement which was/were correct?
[A]. The property of a conductor due to which it opposes the flow of current through it is called resistance.
[B]. The resistance of a conductor depends on length, thickness, nature of material and temperature of the conductor.
[C]. 1 ohm is the resistance of a conductor such that when a potential difference of 1 volt is applied to its ends, a current of 1 ampere flows through it.
[D]. All the above.
Answer: Option D
Explanation:Here, all these statements are correct. Hence, your answer will be option [D].
Q6
Priya is writing some statements, choose the incorrect statement and help him:
[A]. Those substance which have very low electrical resistance are called good conductors.
[B]. Those substances which have comparatively high electrical resistance, are called resistors.
[C]. Those substances which have infinitely high electrical resistance are called insulators.
[D]. The heating element of electric iron is made of nichrome wire which is an insulator.
Answer: Option D
Explanation:The heating element of electric iron is made of nichrome wire which is a resistor.
The electric wires are made of copper which is a good conductor but their covering is made of plastic which is an example of insulator.
Q7
Read the following sentences carefully, and choose the incorrect one:
[A]. Alloy of nickel, chromium, manganese and iron having a resistivity of about 60 times more than that of copper.
[B]. The heating elements of electrical heating appliances such as electric iron and toaster are made of an alloy rather than a pure metal.
[C]. Nichrome undergoes oxidation very easily at a high temperature.
[D]. Nichrome alloy is used for making the heating elements of electrical appliances.
Answer: Option C
Explanation:Nichrome does not undergo oxidation or burn easily even at high temperature. Due to this nichrome wire can be kept red hot without burning or breaking in air.
Q8
An electric fuse works on the:
[A]. Chemical effect of current
[B]. Magnetic effect of current
[C]. Lighting effect of current
[D]. Heating effect of current
Answer: Option D
Explanation: An electric fuse works on the heating effect of current.
Q9
How much energy does a 100 W electric bulb transfer in 1 minute?
[A]. 100 J
[B]. 600 J
[C]. 3600 J
[D]. 6000 J
Answer: Option D
Explanation:Energy transferred, E = power x time = 100 W x 60 s = 6000 J
Q10
The resistance of a wire of length 300 m and cross-section area 1.0 mm2 made of material of resistivity 1.0 × 10−7 Ωm is:
[A]. 2 Ω
[B]. 3 Ω
[C]. 20 Ω
[D]. 30 Ω
Answer: Option D
Explanation:Resistance, R=ρlA
Length, l = 300 m
Cross-section area, A = 1.0 mm2 = 10-6 m2
Resistivity, ρ = 1.0 × 10−7 Ωm
Resistance, R=10−7×30010−6
R = 30 Ω
What is meant by an electric circuit?
A continuous and closed path of an electric current is called an electric circuit.
What is fuse wire and how does it work?
The fuse is placed in series with the device. It consists of a piece of wire made of a metal or an alloy of appropriate melting point, for example aluminium, copper, iron, lead etc. If a current larger than the specified value flows through the circuit, the temperature of the fuse wire increases. This melts the fuse wire and breaks the circuit.
What do you know about a resistor?
A conductor having some appreciable resistance is called a resistor.
What is variable resistance or rheostat?
A component used to regulate current without changing the voltage source is called variable resistance.
Updated CBSE NCERT Solutions
We use to updated NCERT Solutions according to latest updates provide by CBSE or feedback received by the users. We modify the contents as per need of students also. Most of the contents are available in Hindi and English Medium. Feel free to contact us regarding any educational help.