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MCQOPTIONS
This section includes 2637 Mcqs, each offering curated multiple-choice questions to sharpen your 7th Class knowledge and support exam preparation. Choose a topic below to get started.
| 2001. |
Which of the following does NOT contain a heating element? |
| A. | Electric iron |
| B. | Electric heater |
| C. | Electric oven |
| D. | Electric bell |
| Answer» E. | |
| 2002. |
The acting contacts for circuit breakers are made of |
| A. | Stainless steel |
| B. | Hard pressed carbon |
| C. | Porcelain |
| D. | Copper tungsten alloy |
| Answer» E. | |
| 2003. |
Consider the following statements and select the correct option which correctly identifies true (T) and false (F). (i) Iron loses its magnetism easily,(ii) Steel is a hard magnetic material. (iii) Iron is used to make permanent magnet, (iv) Steel is used to make electromagnet, |
| A. | (i)(ii)(iii)(iv)FFTT |
| B. | (i)(ii)(iii)(iv)TTFF |
| C. | (i)(ii)(iii)(iv)TFTF |
| D. | (i)(ii)(iii)(iv)FTFT |
| Answer» C. (i)(ii)(iii)(iv)TFTF | |
| 2004. |
What happens if you place a compass near a current conducting wire? |
| A. | The needle in the compass gets deflected. |
| B. | The needle in the compass gets charged. |
| C. | The needle in the compass becomes hot. |
| D. | The needle in the compass glows brightly. |
| Answer» B. The needle in the compass gets charged. | |
| 2005. |
Why are symbols used for electric components? |
| A. | It makes it easier to draw the circuit diagrams |
| B. | It is essential to draw the circuit diagrams |
| C. | It helps to show the direction of flow of current in a circuit |
| D. | All of the above |
| Answer» B. It is essential to draw the circuit diagrams | |
| 2006. |
Three bulbs A, B and C are connected as shown in figure. The bulbs B and C are identical. If the bulb C is fused, then |
| A. | Brightness of both bulbs A and B will increase |
| B. | Brightness of both bulbs A and B will decrease |
| C. | Brightness of the bulb A decreases and that of bulb B increases |
| D. | None of the bulbs will glow. |
| Answer» D. None of the bulbs will glow. | |
| 2007. |
Pranati has set up a circuit as shown below. Which of the following should she put in the blank box marked X to make the bulb glow more brightly? |
| A. | Bulb |
| B. | Cell |
| C. | Key |
| D. | Wire |
| Answer» C. Key | |
| 2008. |
Which of the following instruments is used to check whether electricity is flowing through a substance or not? |
| A. | Voltmeter |
| B. | Ammeter |
| C. | Tester |
| D. | Cell |
| Answer» D. Cell | |
| 2009. |
The bulb in the circuit shown below does not glow. Which of following labelled parts is responsible for this? |
| A. | 4 |
| B. | 2 |
| C. | 3 |
| D. | 1 |
| Answer» D. 1 | |
| 2010. |
Key or switch in circuit is placed: |
| A. | left side of the battery |
| B. | right side of the battery |
| C. | any where in the circuit |
| D. | near the positive terminal of the bulb |
| Answer» D. near the positive terminal of the bulb | |
| 2011. |
Which of the following statements is incorrect for the given circuit? |
| A. | The wire has no magnetic effect. |
| B. | When compass is kept near to the circuit, it will not show any deflection. |
| C. | The given circuit is incomplete because there is no source of electric energy. |
| D. | Due to battery in this circuit, electric wire behaves as a magnet. |
| Answer» E. | |
| 2012. |
What are the factors upon which the amount of heat produced in a wire depend? (i) Material (ii) Length (iii) Thickness |
| A. | Only (i) and (ii) |
| B. | Only (ii) and (iii) |
| C. | Only (i) and (iii) |
| D. | (i), (ii) and (iii) |
| Answer» E. | |
| 2013. |
Why do electricians wear rubber gloves? |
| A. | They are soft. |
| B. | They are water proof. |
| C. | They are insulators. |
| D. | They are inexpensive. |
| Answer» D. They are inexpensive. | |
| 2014. |
Tungsten is used for the manufacture of an electric bulb because |
| A. | it is malleable |
| B. | it is inexpensive |
| C. | it has a very high melting point |
| D. | it is a good conductor |
| Answer» D. it is a good conductor | |
| 2015. |
Observe the given circuit diagrams (X and Y) and identify the correct statement. |
| A. | Circuit Y is a series circuit. |
| B. | Bulb 2 in circuit X will glow, even when the bulb 1 is fused, and switch \[{{S}_{1}}\] is closed. |
| C. | In circuit Y, bulb 3 will glow if only switch \[{{S}_{2}}\] is closed. |
| D. | Both circuits X and Y are parallel circuits. |
| Answer» D. Both circuits X and Y are parallel circuits. | |
| 2016. |
Match the two columns and select the correct option from codes given below. Column I Column II (a) A bad conductor of electricity but good conductor of heat (i) CFL (b) A wire twisted Nichrome many times in the form of circles (ii) Nichrome (c) Smart eco-friendly bulb (iii) Mica (d) An alloy whose temperature can rise up to \[{{900}^{o}}C\]and used as heating Element (iv) Coil |
| A. | (a)-(iv), (b)-(iii), (c)-(ii), (d)-(i) |
| B. | (a)-(i), (b)-(ii), (c)-(iii), (d)-(iv) |
| C. | (a)-(iii), (b)-(iv), (c)-(i), (d)-(ii) |
| D. | (a)-(ii), (b)-(iv), (c)-(i), (d)-(iii) |
| Answer» D. (a)-(ii), (b)-(iv), (c)-(i), (d)-(iii) | |
| 2017. |
Marking on a bulb is 60 W, 220 V. What does it signify? |
| A. | The bulb is connected across the 220 volts, 60 joules of energy is consumed for every second. |
| B. | The bulb is connected across 220 volts, 60 joules of energy is released. |
| C. | 60 unit of current will flow in the bulb. |
| D. | 220 unit of current will flow in the bulb. |
| Answer» B. The bulb is connected across 220 volts, 60 joules of energy is released. | |
| 2018. |
When current is passed through a conductor, the heat produced in it depends upon I. The material of the conductor II. The current flowing through the conductor III. The time for which the current flows. |
| A. | I and II only |
| B. | I and III only |
| C. | II and III only |
| D. | All I, II and III |
| Answer» E. | |
| 2019. |
Which symbol of the component is represented here? |
| A. | Switch in the ON position |
| B. | Switch in the OFF position |
| C. | Circuit breaker |
| D. | Battery |
| Answer» C. Circuit breaker | |
| 2020. |
DIRECTIONS: Read the passage given below and answer the questions that follow. Passage ? 1 Observe the flow chart given below and answer the questions that follow: \[\text{Magnesium+Oxygen}\xrightarrow{\text{heat}}\text{''A''}\xrightarrow{\text{Water}}\text{''B''}\xrightarrow[\text{solution}]{\text{Red litmus}}\text{''C''}\] "C" in it indicates that |
| A. | Red litmus when added to "B", no change in colour occurs. |
| B. | Red litmus when added to "B" changes to blue. |
| C. | Red litmus when added to "B" changes to green. |
| D. | Red litmus when added to "B" it gives a colorless solution |
| Answer» C. Red litmus when added to "B" changes to green. | |
| 2021. |
The given figure shows the colour changes in test tubes I, II and III, when China rose indicator is added to them. The respective solutions in test tubes I, II and III are |
| A. | Sugar solution Lime water Baking powder |
| B. | Sugar solution Lemon juice Vinegar |
| C. | Lime water Sugar solution Lemon juice |
| D. | Lemon juice Sugar solution Lime water |
| Answer» E. | |
| 2022. |
A substance X is found in the milk of magnesia. What is X? |
| A. | An acid |
| B. | A base |
| C. | Water |
| D. | A salt |
| Answer» C. Water | |
| 2023. |
Caustic soda is the common name for: |
| A. | \[\text{Mg(OH}{{\text{)}}_{\text{2}}}\] |
| B. | \[\text{KOH}\] |
| C. | \[\text{Ca(OH}{{\text{)}}_{\text{2}}}\] |
| D. | \[\text{NaOH}\] |
| Answer» E. | |
| 2024. |
A blue litmus paper was first dipped I dilute hydrochloric acid and then in dilute sodium hydroxide solution. It was observed that the colour of the litmus paper: |
| A. | changed to red |
| B. | changed first to red and then to blue |
| C. | changed blue to colourless |
| D. | remained blue in both solutions. |
| Answer» C. changed blue to colourless | |
| 2025. |
DIRECTIONS: Read the passage given below and answer the questions that follow. Passage - 2 Three different substances were taken and tested with litmus paper. The results are given below. Based on the results answer the questions 43 to 48. Type of Litmus X Y Z Red litmus turns blue no change no change Blue litmus no litmus turns red no change How will the substance X behave with phenolphthalein? |
| A. | It turns pink |
| B. | It remains colorless |
| C. | It turns blue |
| D. | It turns red |
| Answer» B. It remains colorless | |
| 2026. |
Which of the following statements are correct? I. The tangy taste of cola drinks is due to carbonic acid which is an organic acid. II. Inorganic acids are prepared artificially in the industries and are extremely corrosive. III. Hydrochloric acid reacts with metals to varying degrees therefore, it is stored in glass bottles. IV. Organic acids are weak acids and are used as food supplements. |
| A. | I, II and III only |
| B. | I and IV only |
| C. | II and IV only |
| D. | All of these |
| Answer» D. All of these | |
| 2027. |
What change does colourless phenolphthalein undergo in acidic and neutral solutions? |
| A. | Remains colourless |
| B. | Turns pink |
| C. | Turns red |
| D. | Turns green |
| Answer» B. Turns pink | |
| 2028. |
Kartik performed the following experiment by taking few solutions and phenolphthalein indicator. Identify p, q and r in his experiment. |
| A. | p \[\to \]Acid, q \[\to \]Acid, r\[\to \]Base |
| B. | p \[\to \] Base, q\[\to \] Acid, r\[\to \] Base |
| C. | p \[\to \] Base, q\[\to \] Base, r\[\to \]Acid |
| D. | p \[\to \] Base, q\[\to \] Acid, r\[\to \]Acid |
| Answer» C. p \[\to \] Base, q\[\to \] Base, r\[\to \]Acid | |
| 2029. |
Reaction of an acid with a base is: |
| A. | decomposition |
| B. | combination |
| C. | redox |
| D. | neutralization |
| Answer» E. | |
| 2030. |
DIRECTIONS: Read the passage given below and answer the questions that follow. Passage - 4 Indicators change their colour when added to a solution containing an acidic or a basic substance. Turmeric, litmus, China rose petals (Gudhal), etc., are some naturally occurring indicators. Naturally occurring indicator litmus |
| A. | is extracted from lichens |
| B. | has available as red and blue litmus paper |
| C. | has purple colour in distilled water |
| D. | All the above are correct |
| Answer» E. | |
| 2031. |
An indicator prepared from turmeric (Haldi) is added to a strong alkali solution. What colour does the indicator change to? |
| A. | Yellow |
| B. | Brick red |
| C. | Orange |
| D. | Blue |
| Answer» C. Orange | |
| 2032. |
Ishaan tested the nature of a few common substances with different indicators and recorded his observations as follows :Substance P turned methyl orange yellow.Substance Q turned phenolphthalein colorless.Substance R did not have any effect on blue or red litmus.Substance S turned China rose indicator green.P, Q, R and S could be respectively |
| A. | Lemon juice, fermented milk, salt solution and milk of magnesia. |
| B. | Sugar solution, vinegar, water and curd. |
| C. | Lime water, apple juice, sugar solution and saliva |
| D. | None of these. |
| Answer» D. None of these. | |
| 2033. |
Which acid is used in the making of synthetic vinegar? |
| A. | Formic acid |
| B. | Acetic acid |
| C. | Sulphuric acid |
| D. | Nitric acid |
| Answer» C. Sulphuric acid | |
| 2034. |
DIRECTIONS: Read the passage given below and answer the questions that follow. Passage - 1 The rain which contains a higher level of acid than normal is called acid rain. Acidic gases like sulphur dioxide, nitrogen dioxide and carbon dioxide which are released as pollutants during the burning of various types of faels dissolve in rain drops and when these rain drops fall as rain on earth, we call it acid rain. \[\text{C}{{\text{O}}_{\text{2}}}\] dissolves in a water to form: |
| A. | \[\text{C+}{{\text{H}}_{\text{2}}}+{{\text{O}}_{\text{2}}}\] |
| B. | \[\text{C}{{\text{H}}_{\text{4}}}\] |
| C. | \[\text{CO}\] |
| D. | carbonic acid |
| Answer» E. | |
| 2035. |
............... is an acid-base indicator, its colour is yellow in basic medium and pink in acidic medium. |
| A. | Phenolphthalein |
| B. | Methyl orange |
| C. | Litmus |
| D. | Both (a) and (b) are correct |
| Answer» C. Litmus | |
| 2036. |
A base is a substance that |
| A. | feels slippery |
| B. | tastes sour |
| C. | reacts with metals to produce hydrogen gas |
| D. | and (c) |
| Answer» E. | |
| 2037. |
Antacids contain - |
| A. | Strong acid |
| B. | Weak base |
| C. | Strong base |
| D. | Weak acid |
| Answer» C. Strong base | |
| 2038. |
The two types of litmus paper are: |
| A. | blue and red |
| B. | blue and yellow |
| C. | red and green |
| D. | yellow and red |
| Answer» B. blue and yellow | |
| 2039. |
Which of the following chemicals are used to neutralize the basic nature of soil? |
| A. | Quicklime |
| B. | Organic matter |
| C. | Slaked lime |
| D. | Baking soda |
| Answer» C. Slaked lime | |
| 2040. |
Following observation were recorded upon performing experiments with sample 'A' and sample 'B'. (i) When 2-3 drops of phenolphthalein are added to sample 'A' it becomes pink. (ii) When equal quantities of two samples are added in a test-tube, the test-tube becomes hot. |
| A. | sample 'A' is basic |
| B. | sample 'B' is acidic |
| C. | (ii) observation confirms neutralisation |
| D. | All the above are correct |
| Answer» E. | |
| 2041. |
DIRECTIONS: The questions in this segment consists of two statements, one labeled as "Assertion A" and the other labeled as "Reason R". You are to examine these two statements carefully and decide if the Assertion A and Reason R are individually true and if so, whether the reason is a correct explanation of the assertion. Select your answers to these items using codes given below. Assertion (A): Sodium hydroxide is an alkali. Reason (R): All bases are alkalies. |
| A. | Both A and R are true and R is the correct explanation of A. |
| B. | Both A and R are true but R is not the correct explanation of A. |
| C. | A is true but R is false. |
| D. | A is false but R is true. |
| Answer» D. A is false but R is true. | |
| 2042. |
A base reacts with an acid to form salt and water. What is this reaction called? |
| A. | Oxidation reaction |
| B. | Neutralization reaction |
| C. | Reduction reaction |
| D. | Biochemical reaction |
| Answer» C. Reduction reaction | |
| 2043. |
Which is responsible for the damaging effects caused by acid rain? |
| A. | Carbonic acid |
| B. | Sulphuric acid |
| C. | Nitric acid |
| D. | All of these |
| Answer» E. | |
| 2044. |
DIRECTIONS: Read the passage given below and answer the questions that follow. Passage - 4 Indicators change their colour when added to a solution containing an acidic or a basic substance. Turmeric, litmus, China rose petals (Gudhal), etc., are some naturally occurring indicators. Which of the following is correct about the indicator China rose? |
| A. | It is a natural indicator. |
| B. | It gives green colour in an acidic solution. |
| C. | It gives magenta colour in a basic solution. |
| D. | All the above are correct. |
| Answer» B. It gives green colour in an acidic solution. | |
| 2045. |
DIRECTION: Match Column-I with Column-II and select the correct answer using the codes given below the columns. Column - I Column - II (A) Slaked lime (p) Used in batteries (B) Vinegar (q) Sour in taste (C) Sulphuric acid (r) Apply on bee?s sting (D) Turmeric indicator (s) Turns brown with the application of soap |
| A. | A\[\to \] (s), B\[\to \] (q), C\[\to \] (p), D\[\to \] (r) |
| B. | A\[\to \] (r), B\[\to \] (q), C\[\to \] (p), D\[\to \] (s) |
| C. | A\[\to \] (q), B\[\to \] (r), C\[\to \] (p), D\[\to \] (s) |
| D. | A\[\to \] (r), B\[\to \] (q), C\[\to \] (s), D\[\to \] (p) |
| Answer» C. A\[\to \] (q), B\[\to \] (r), C\[\to \] (p), D\[\to \] (s) | |
| 2046. |
DIRECTIONS: Match Column-I with Column-II and select the correct answer using the codes given below the columns. Column - I (Common name) Column - II (Chemical name/ Chemical present) (A) Slaked lime (p) Zinc carbonate (B) Baking soda (q) Calcium hydroxide (C) Calamine solution (r) Sodium bicarbonate (D) Milk of Magnesia (s) Magnesium hydroxide |
| A. | (A) \[\to \] (p), (B) \[\to \] (q), (C) \[\to \] (r), (D) \[\to \] (s) |
| B. | (A) \[\to \] (q), (B) \[\to \] (r), (C) \[\to \] (p), (D) \[\to \] (s) |
| C. | (A) \[\to \] (r), (B) \[\to \] (s), (C) \[\to \] (q), (D) \[\to \] (p) |
| D. | (A) \[\to \] (s), (B) \[\to \] (p), (C) \[\to \] (q), (D) \[\to \] (r) |
| Answer» C. (A) \[\to \] (r), (B) \[\to \] (s), (C) \[\to \] (q), (D) \[\to \] (p) | |
| 2047. |
Read the given statements and select the correct option. Statement 1: To neutralise the effect of a bee sting, that portion of the body is rubbed with moist baking soda. Statement 2: Baking soda contains sodium carbonate which neutralises the effect of acid injected by bee sting. |
| A. | Both statements 1 and 2 are true and statement 2 is the correct explanation of statement 1. |
| B. | Both statements 1 and 2 are true but statement 2 is not the correct explanation of statement 1. |
| C. | Statement 1 is true and statement 2 is false. |
| D. | Both statements 1 and 2 are false. |
| Answer» D. Both statements 1 and 2 are false. | |
| 2048. |
Non-metallic oxides react with water to form |
| A. | alkaline solution |
| B. | acidic solution |
| C. | neutral solution |
| D. | None of these |
| Answer» C. neutral solution | |
| 2049. |
Phenolphthalein turns_______ in acidic and neutral solutions. |
| A. | colourless |
| B. | pink |
| C. | red |
| D. | green |
| Answer» B. pink | |
| 2050. |
Observe the given figure carefully and choose the incorrect statement(s). 1. Large volume of acid should be added to a small volume of water slowly. 2. The figure represents the process of concentrating dilute\[{{H}_{2}}S{{O}_{4}}\]. 3. The process involves release of a large amount of heat. 4. Water should not be stirred. |
| A. | 1 and 4 only |
| B. | 2 and 3 only |
| C. | 1, 2 and 4 only |
| D. | 2 only |
| Answer» D. 2 only | |