Physics 10th : MCQ 2
1. Which of the following increases the strength of an electromagnet ? āĻ¤āĻ˛ā§° āĻā§āĻ¨āĻā§ āĻā§°āĻŋāĻ˛ā§ āĻāĻ˛ā§āĻā§āĻā§ā§°ā§āĻŽā§āĻāĻ¨ā§āĻā§° āĻļāĻā§āĻ¤āĻŋ āĻŦā§āĻĻā§āĻ§āĻŋ āĻĒāĻžāĻ¯āĻŧ ?
A) Reduce the current (āĻŦāĻŋāĻĻā§āĻ¯ā§ā§ āĻ§āĻžā§°āĻž āĻāĻŽā§ā§ąāĻž)
B) Reduce the number of turns (āĻĒāĻžāĻ āĻāĻŽā§ā§ąāĻž)
C) Insert an iron core (āĻ˛ā§āĻšāĻžā§° āĻā§ā§° āĻ¸āĻāĻ¯ā§āĻāĻ¨ āĻā§°āĻž)
D) Increase resistance (ā§°ā§āĻ§ āĻŦā§āĻĻā§āĻ§āĻŋ āĻā§°āĻž)
Ans / āĻāĻ¤ā§āĻ¤ā§°: C) Insert an iron core (āĻ˛ā§āĻšāĻžā§° āĻā§ā§° āĻ¸āĻāĻ¯ā§āĻāĻ¨ āĻā§°āĻž)
Explanation / āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: Iron core increases magnetic field strength. āĻ˛ā§āĻšāĻžā§° āĻā§ā§° āĻŦā§āĻ¯ā§ąāĻšāĻžā§° āĻā§°āĻŋāĻ˛ā§ āĻā§āĻŽā§āĻŦāĻā§āĻ¯āĻŧ āĻā§āĻˇā§āĻ¤ā§ā§° āĻļāĻā§āĻ¤āĻŋāĻļāĻžāĻ˛ā§ āĻšāĻ¯āĻŧāĨ¤
2. A ray of light strikes a plane mirror at 40°. What is the angle between the incident and reflected ray ? āĻāĻāĻž āĻĒā§āĻšā§°ā§° ā§°āĻļā§āĻŽāĻŋ āĻāĻāĻ¨ āĻ¸āĻŽāĻ¤āĻ˛ āĻĻāĻžāĻĒā§āĻ¨āĻ¤ 40° āĻā§āĻŖāĻ¤ āĻĒāĻ¤āĻŋāĻ¤ āĻšāĻ¯āĻŧāĨ¤ āĻĒāĻ¤āĻŋāĻ¤ āĻā§°ā§ āĻĒā§ā§°āĻ¤āĻŋāĻĢāĻ˛āĻŋāĻ¤ ā§°āĻļā§āĻŽāĻŋā§° āĻŽāĻžāĻā§° āĻā§āĻŖ āĻāĻŋāĻŽāĻžāĻ¨ ?
A) 90° / B) 80° / C) 40° / D) 50°
Ans / āĻāĻ¤ā§āĻ¤ā§°: B) 80°
Explanation / āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: Angle of incidence = angle of reflection = 40° → total = 80°.
āĻĒāĻ¤āĻŋāĻ¤ āĻā§āĻŖ = āĻĒā§ā§°āĻ¤āĻŋāĻĢāĻ˛āĻ¨ āĻā§āĻŖ = 40° → āĻŽā§āĻ = 80°āĨ¤
3. Fuses in electrical circuits are based on which effect of electric current ? āĻŦā§āĻĻā§āĻ¯ā§āĻ¤āĻŋāĻ āĻĒā§°āĻŋāĻĒāĻĨāĻ¤ āĻĢāĻŋāĻāĻ āĻā§āĻ¨āĻā§ āĻĒā§ā§°āĻāĻžā§ąā§° āĻāĻĒā§°āĻ¤ āĻāĻ§āĻžā§°āĻŋāĻ¤ ?
A) Magnetic effect (āĻā§āĻŽā§āĻŦāĻā§āĻ¯āĻŧ) / B) Chemical effect (ā§°āĻžāĻ¸āĻžāĻ¯āĻŧāĻ¨āĻŋāĻ) / C) Heating effect (āĻ¤āĻžāĻĒā§āĻ¯āĻŧ) / D) Electrostatic effect (āĻŦāĻŋāĻĻā§āĻ¯ā§ā§āĻ¸ā§āĻĨāĻŋā§°)
Ans / āĻāĻ¤ā§āĻ¤ā§°: C) Heating effect (āĻ¤āĻžāĻĒā§āĻ¯āĻŧ)
Explanation / āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: Fuse melts due to heating effect of current. āĻ¤āĻžāĻĒā§āĻ¯āĻŧ āĻĒā§ā§°āĻāĻžā§ąā§° āĻŦāĻžāĻŦā§ āĻĢāĻŋāĻāĻ āĻāĻ˛āĻŋ āĻ¯āĻžāĻ¯āĻŧāĨ¤
4. How much work is done in moving a charge of 5 C across a potential difference of 10 V ? ā§Ģ C āĻā§ąā§āĻļāĻ ā§§ā§Ļ V āĻŦāĻŋāĻā§ą āĻĒāĻžā§°ā§āĻĨāĻā§āĻ¯ā§°ā§ āĻ¸ā§āĻĨāĻžāĻ¨āĻžāĻ¨ā§āĻ¤ā§° āĻā§°āĻŋāĻ˛ā§ āĻāĻŋāĻŽāĻžāĻ¨ āĻāĻžāĻŽ āĻšāĻ¯āĻŧ ?
A) 5 J / B) 0.5 J / C) 50 J / D) 100 J
Ans / āĻāĻ¤ā§āĻ¤ā§°: C) 50 J
Explanation / āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: Work = Q × V = 5 × 10 = 50 J. āĻāĻžāĻŽ = āĻā§ąā§āĻļ × āĻŦāĻŋāĻā§ą = ā§Ģā§Ļ āĻā§āĻ˛āĨ¤
5. Bleaching powder reacts with COâ to release a compound of . āĻŦā§āĻ˛āĻŋāĻāĻŋāĻ āĻĒāĻžāĻāĻĄāĻžā§°ā§ COâ ā§° āĻ¸ā§āĻ¤ā§ āĻŦāĻŋāĻā§ā§°āĻŋāĻ¯āĻŧāĻž āĻā§°āĻŋ āĻā§āĻ¨āĻā§ āĻŽā§āĻā§āĻ¤ āĻā§°ā§ ?
A) Chlorine (āĻā§āĻ˛’ā§°āĻŋāĻ¨) / B) Phosphorus / C) Sulphur / D) Sodium
Ans / āĻāĻ¤ā§āĻ¤ā§°: A) Chlorine (āĻā§āĻ˛’ā§°āĻŋāĻ¨)
Explanation / āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: Bleaching powder releases chlorine gas. āĻŦā§āĻ˛āĻŋāĻāĻŋāĻ āĻĒāĻžāĻāĻĄāĻžā§°ā§ āĻā§āĻ˛’ā§°āĻŋāĻ¨ āĻā§āĻ āĻŽā§āĻā§āĻ¤ āĻā§°ā§āĨ¤
6. Which salt is neutral in nature ? āĻ¤āĻ˛ā§° āĻā§āĻ¨āĻā§ āĻ˛ā§ąāĻŖ āĻ¨āĻŋā§°āĻĒā§āĻā§āĻˇ āĻ¸ā§āĻŦāĻāĻžā§ąā§° ?
A) NaâCOâ / B) NHâCl / C) NaNOâ / D) CuSOâ
Ans / āĻāĻ¤ā§āĻ¤ā§°: C) NaNOâ
Explanation / āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: NaNOâ is formed from strong acid and strong base. NaNOâ āĻļāĻā§āĻ¤āĻŋāĻļāĻžāĻ˛ā§ āĻ āĻŽā§āĻ˛ āĻā§°ā§ āĻā§āĻˇāĻžā§°ā§° āĻĒā§°āĻž āĻāĻ āĻŋāĻ¤āĨ¤
7. Crystallization is a method of separating āĻ¸ā§āĻĢāĻāĻŋāĻā§āĻā§°āĻŖ āĻĒāĻĻā§āĻ§āĻ¤āĻŋ āĻŦā§āĻ¯ā§ąāĻšāĻžā§° āĻā§°āĻž āĻšāĻ¯āĻŧ -
A) Constituents of milk B) Impurities from a compound C) Dissolved oxygen from water
D) Ionic salts from water
Ans / āĻāĻ¤ā§āĻ¤ā§°: B) Impurities from a compound
Explanation / āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: Crystallization removes impurities from solids. āĻ¸ā§āĻĢāĻāĻŋāĻā§āĻā§°āĻŖā§ āĻāĻ āĻŋāĻ¨ āĻĒāĻĻāĻžā§°ā§āĻĨā§° āĻ āĻļā§āĻĻā§āĻ§āĻŋ āĻāĻāĻ¤ā§°āĻžāĻ¯āĻŧāĨ¤
8. In an electric circuit, bulbs A and B are identical, but B glows brighter than A. Why ? āĻāĻāĻž āĻŦā§āĻĻā§āĻ¯ā§āĻ¤āĻŋāĻ āĻĒā§°āĻŋāĻĒāĻĨāĻ¤ A āĻā§°ā§ B āĻŦāĻžāĻ˛ā§āĻŦ āĻāĻā§āĻ, āĻāĻŋāĻ¨ā§āĻ¤ā§ B āĻ āĻ§āĻŋāĻ āĻāĻā§āĻā§āĻŦāĻ˛āĨ¤ āĻāĻŋāĻ¯āĻŧ ?
A) Bulb B has higher resistance B) Bulb A has higher resistance C) More current flows through bulb B D) Less current flows through bulb B
Ans / āĻāĻ¤ā§āĻ¤ā§°: C) More current flows through bulb B
Explanation / āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: Brightness ∝ current through the bulb. āĻŦāĻžāĻ˛ā§āĻŦā§° āĻāĻā§āĻā§āĻŦāĻ˛āĻ¤āĻž āĻ§āĻžā§°āĻžā§° āĻāĻĒā§°āĻ¤ āĻ¨āĻŋā§°ā§āĻā§° āĻā§°ā§āĨ¤
9. Which optical device cannot produce a virtual image ? āĻā§āĻ¨āĻā§ āĻĻā§°ā§āĻļāĻ¨ā§āĻ¯āĻŧ āĻ¯āĻ¨ā§āĻ¤ā§ā§°ā§ āĻā§āĻ¤āĻŋāĻ¯āĻŧāĻžāĻ āĻāĻžāĻ˛ā§āĻĒāĻ¨āĻŋāĻ (virtual) āĻĒā§ā§°āĻ¤āĻŋāĻā§āĻāĻŦāĻŋ āĻā§āĻĒāĻ¨ā§āĻ¨ āĻā§°āĻŋāĻŦ āĻ¨ā§ā§ąāĻžā§°ā§ ?
A) Convex lens / āĻāĻ¤ā§āĻ¤āĻ˛ āĻ˛ā§āĻ¨ā§āĻ¸ / B) Concave mirror / āĻ ā§ąāĻ¤āĻ˛ āĻĻāĻžāĻĒā§āĻ¨ / C) Convex mirror / āĻāĻ¤ā§āĻ¤āĻ˛ āĻĻāĻžāĻĒā§āĻ¨ / D) Concave lens / āĻ ā§ąāĻ¤āĻ˛ āĻ˛ā§āĻ¨ā§āĻ¸
Ans / āĻāĻ¤ā§āĻ¤ā§°: A) Convex lens / āĻāĻ¤ā§āĻ¤āĻ˛ āĻ˛ā§āĻ¨ā§āĻ¸
Explanation / āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: A convex lens mainly forms real images (except when object is between O and F). āĻāĻ¤ā§āĻ¤āĻ˛ āĻ˛ā§āĻ¨ā§āĻ¸ā§ āĻ¸āĻžāĻ§āĻžā§°āĻŖāĻ¤ā§ āĻŦāĻžāĻ¸ā§āĻ¤ā§ą āĻĒā§ā§°āĻ¤āĻŋāĻā§āĻāĻŦāĻŋ āĻāĻ āĻ¨ āĻā§°ā§āĨ¤
10. A battery converts chemical energy into electrical energy by - āĻŦā§āĻāĻžā§°ā§āĻ¯āĻŧā§ ā§°āĻžāĻ¸āĻžāĻ¯āĻŧāĻ¨āĻŋāĻ āĻļāĻā§āĻ¤āĻŋāĻ āĻŦā§āĻĻā§āĻ¯ā§āĻ¤āĻŋāĻ āĻļāĻā§āĻ¤āĻŋāĻ˛ā§ ā§°ā§āĻĒāĻžāĻ¨ā§āĻ¤ā§° āĻā§°ā§ -
A) Electrolysis / āĻŦāĻŋāĻĻā§āĻ¯ā§ā§ āĻŦāĻŋāĻļā§āĻ˛ā§āĻˇāĻŖ / B) Heating effect / āĻ¤āĻžāĻĒā§āĻ¯āĻŧ āĻĒā§ā§°āĻāĻžā§ą / C) Chemical reaction / ā§°āĻžāĻ¸āĻžāĻ¯āĻŧāĻ¨āĻŋāĻ āĻŦāĻŋāĻā§ā§°āĻŋāĻ¯āĻŧāĻž / D) Magnetic effect / āĻā§āĻŽā§āĻŦāĻā§āĻ¯āĻŧ āĻĒā§ā§°āĻāĻžā§ą
Ans / āĻāĻ¤ā§āĻ¤ā§°: C) Chemical reaction / ā§°āĻžāĻ¸āĻžāĻ¯āĻŧāĻ¨āĻŋāĻ āĻŦāĻŋāĻā§ā§°āĻŋāĻ¯āĻŧāĻž
Explanation / āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: Electricity is produced due to chemical reactions inside the battery. āĻŦā§āĻāĻžā§°ā§ā§° āĻāĻŋāĻ¤ā§°ā§° ā§°āĻžāĻ¸āĻžāĻ¯āĻŧāĻ¨āĻŋāĻ āĻŦāĻŋāĻā§ā§°āĻŋāĻ¯āĻŧāĻžā§° āĻĢāĻ˛āĻ¤ā§āĻ āĻŦāĻŋāĻĻā§āĻ¯ā§ā§ āĻā§āĻĒāĻ¨ā§āĻ¨ āĻšāĻ¯āĻŧāĨ¤
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11. Which colour has the highest speed in a glass prism ? āĻāĻžāĻāĻā§° āĻĒā§ā§°āĻŋāĻāĻŽāĻ¤ āĻā§āĻ¨āĻā§ ā§°āĻā§° āĻāĻ¤āĻŋ āĻ¸ā§°ā§āĻŦāĻžāĻ§āĻŋāĻ ?
A) Red / ā§°āĻāĻž / B) Green / āĻ¸ā§āĻāĻā§āĻ¯āĻŧāĻž | C) Blue / āĻ¨ā§āĻ˛āĻž | D) Violet / āĻŦā§āĻā§āĻ¨ā§
Ans / āĻāĻ¤ā§āĻ¤ā§°: A) Red / ā§°āĻāĻž
Explanation / āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: Red light has the longest wavelength and highest speed in glass. ā§°āĻāĻž āĻĒā§āĻšā§°ā§° āĻ¤ā§°āĻāĻāĻĻā§ā§°ā§āĻā§āĻ¯ āĻŦā§āĻāĻŋ, āĻāĻ¤āĻŋāĻ āĻŦā§āĻāĻŋāĨ¤
12. A bulb glows brighter when current is - āĻŦāĻžāĻ˛ā§āĻŦ āĻ āĻ§āĻŋāĻ āĻāĻā§āĻā§āĻŦāĻ˛ āĻšāĻ¯āĻŧ āĻ¯ā§āĻ¤āĻŋāĻ¯āĻŧāĻž āĻŦāĻŋāĻĻā§āĻ¯ā§ā§ āĻ§āĻžā§°āĻž -
A) Becomes zero / āĻļā§āĻ¨ā§āĻ¯ āĻšāĻ¯āĻŧ / B) Becomes constant / āĻ¸ā§āĻĨāĻŋā§° āĻšāĻ¯āĻŧ / C) Increased / āĻŦā§āĻĻā§āĻ§āĻŋ āĻĒāĻžāĻ¯āĻŧ / D) Decreased / āĻāĻŽā§
Ans / āĻāĻ¤ā§āĻ¤ā§°: C) Increased / āĻŦā§āĻĻā§āĻ§āĻŋ āĻĒāĻžāĻ¯āĻŧ
Explanation / āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: Brightness depends on current. More current → more brightness. āĻāĻā§āĻā§āĻŦāĻ˛āĻ¤āĻž āĻ§āĻžā§°āĻžā§° āĻāĻĒā§°āĻ¤ āĻ¨āĻŋā§°ā§āĻā§° āĻā§°ā§āĨ¤
13. When soap solution is added to water, its pH will - āĻĒāĻžāĻ¨ā§āĻ¤ āĻāĻžāĻŦā§āĻ¨ā§° āĻĻā§ā§°ā§ąāĻŖ āĻ¯ā§āĻ āĻā§°āĻŋāĻ˛ā§ pH -
A) Become 7 / B) Become 2 - 4 / C) Increase / D) Decrease
Ans / āĻāĻ¤ā§āĻ¤ā§°: C
Explanation / āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: Soap is basic, so pH increases. āĻāĻžāĻŦā§āĻ¨ āĻā§āĻˇāĻžā§°ā§āĻ¯āĻŧ, āĻ¸ā§āĻ¯āĻŧā§ pH āĻŦā§āĻĻā§āĻ§āĻŋ āĻĒāĻžāĻ¯āĻŧāĨ¤
14. Methane burns in air to form COâ and HâO. This is a - āĻŽāĻŋāĻĨā§āĻ¨ āĻŦāĻžāĻ¯āĻŧā§āĻ¤ āĻā§āĻŦāĻ˛āĻŋ COâ āĻā§°ā§ āĻĒāĻžāĻ¨ā§ āĻā§āĻĒāĻ¨ā§āĻ¨ āĻā§°ā§āĨ¤ āĻāĻāĻā§ -
A) Decomposition reaction / B) Double displacement / C) Combination reaction / D) Neutralisation
Ans / āĻāĻ¤ā§āĻ¤ā§°: C) Combination reaction
Explanation / āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: Substances combine with oxygen → combination reaction. āĻ āĻā§āĻ¸āĻŋāĻā§āĻ¨ā§° āĻ¸ā§āĻ¤ā§ āĻŽāĻŋāĻ˛āĻŋāĻ¤ āĻšā§ā§ąāĻž āĻŦāĻŋāĻā§ā§°āĻŋāĻ¯āĻŧāĻžāĨ¤
15. Which of the following has the lowest pH ? āĻ¤āĻ˛ā§° āĻā§āĻ¨āĻā§ā§° pH āĻ¸ā§°ā§āĻŦāĻ¨āĻŋāĻŽā§āĻ¨ ?
A) Sodium hydroxide / B) Lemon juice / C) Antacid / D) Soap solution
Ans / āĻāĻ¤ā§āĻ¤ā§°: B) Lemon juice
Explanation / āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: Lemon juice is acidic, so lowest pH. āĻ¨ā§āĻŽā§ā§° ā§°āĻ¸ āĻ āĻŽā§āĻ˛ā§āĻ¯āĻŧāĨ¤
16. Which plant gets nutrition from insects ? āĻā§āĻ¨āĻā§ āĻāĻĻā§āĻāĻŋāĻĻā§ āĻĒāĻ¤āĻāĻā§° āĻĒā§°āĻž āĻĒā§āĻˇā§āĻāĻŋ āĻ˛āĻžāĻ āĻā§°ā§ ?
A) Mushroom / B) Cuscuta / C) Pitcher plant / D) Orchid
Ans / āĻāĻ¤ā§āĻ¤ā§°: C) Pitcher plant
Explanation / āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: Pitcher plant traps insects for nutrition. āĻĒāĻŋāĻāĻžā§° āĻĒā§āĻ˛āĻžāĻ¨ā§āĻā§ āĻĒāĻ¤āĻāĻ āĻ§ā§°āĻŋ āĻĒā§āĻˇā§āĻāĻŋ āĻ˛āĻžāĻ āĻā§°ā§āĨ¤
17. Which blood vessel has thin walls and reaches every cell ? āĻā§āĻ¨āĻā§ ā§°āĻā§āĻ¤āĻ¨āĻ˛ā§ā§° āĻĒā§ā§°āĻžāĻā§ā§° āĻĒāĻžāĻ¤āĻ˛ āĻā§°ā§ āĻ¸āĻāĻ˛ā§ āĻā§āĻˇāĻ˛ā§ āĻ¯āĻžāĻ¯āĻŧ ?
A) Capillaries / B) Veins / C) Arteries / D) Lymph
Ans / āĻāĻ¤ā§āĻ¤ā§°: A) Capillaries
Explanation / āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: Capillaries connect arteries and veins and reach cells. āĻā§āĻĒāĻŋāĻ˛āĻžā§°ā§āĻ¯āĻŧā§ āĻā§āĻˇāĻ˛ā§ āĻ āĻā§āĻ¸āĻŋāĻā§āĻ¨ āĻā§°ā§ āĻĒā§āĻˇā§āĻāĻŋ āĻĻāĻŋāĻ¯āĻŧā§āĨ¤
18. Which prism arrangement produces maximum dispersion of light ? āĻā§āĻ¨āĻā§ āĻĒā§ā§°āĻŋāĻāĻŽ āĻŦāĻŋāĻ¨ā§āĻ¯āĻžāĻ¸ā§ āĻ¸ā§°ā§āĻŦāĻžāĻ§āĻŋāĻ āĻŦāĻŋāĻā§āĻā§ā§°āĻŖ āĻāĻāĻžāĻ¯āĻŧ ?
Ans / āĻāĻ¤ā§āĻ¤ā§°: Prisms placed in opposite orientation (A)
Explanation / āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: Opposite orientation increases angular separation of colours. āĻŦāĻŋāĻĒā§°ā§āĻ¤ āĻŦāĻŋāĻ¨ā§āĻ¯āĻžāĻ¸ā§ ā§°āĻā§° āĻŦāĻŋāĻā§āĻā§ā§°āĻŖ āĻŦā§āĻĻā§āĻ§āĻŋ āĻā§°ā§āĨ¤