Sample Paper: Term-1:2021-22 - Class 10th Science
Science Term-1 MCQs:D
Question No. 31 to 34 consists of two statements Assertion (A) and Reason (R).
Answer these questions selecting the appropriate option given below:
(A) Both A and R are true and R is the correct Explanation of A
(B) Both A and R are true and R is not the correct Explanation of A
(C) A is true but R is false
(D) A is False but R is true
Question (31) Assertion : The decomposition reactions require energy either in the form of heat, light or electricity for breaking down the reactants.
Reason: Reactions in which energy is absorbed are known as endothermic reactions.
Answer (C) (B) Both A and R are true and R is not the correct Explanation of A
Explanation
Yes, assertion is true because energy is needed to break down the reaction.
The reason is also true as reactions in which energy is absorbed is endothermic reaction.
But R is not the correct Explanation of given Assertion.
Thus, the correct answer is, option (B) Both A and R are true and R is not the correct Explanation of A
Question (32) Assertion : Baking powder is used in making cake instead of using only baking soda.
Reason: Baking powder contains tartaric acid which reacts with sodium carbonate and removes bitter taste.
Answer : (A) Both A and R are true and R is the correct Explanation of A
Question (33) Assertion : The rate of breathing in Terrestrial animals is much faster than aquatic organisms.
Reason: The amount of oxygen available to the Terrestrial organism is more than the amount of oxygen available to the Aquatic organisms.
Answer (D) A is False but R is true
Explanation :
The given Assertion is wrong. The rate of breathing in terrestrial organism is slower than that of aquatic animals.
And the reason as given, the amount of oxygen available to the Terrestrial organism is more than the amount of oxygen available to the Aquatic animal is true.
Thus, the correct answer is (D) A is False but R is true
Question (34) Assertion: Higher is the refractive index of a medium, lesser is the velocity of light in the that medium.
Reason: Refractive index is inversely proportional to velocity.
Answer : (A) Both A and R are true and R is the correct Explanation of A
Question (35) The table given below shows the reaction of few elements with acids and bases to evolve Hydrogen gas.
| Element | Acid | Base |
|---|---|---|
| A | x | x |
| B | ✓ | ✓ |
| C | ✓ | x |
| D | ✓ | ✓ |
Which of these elements form amphoteric oxides?
(A) A and B
(B) B and D
(C) A and C
(D) B and C
Answer (B) B and D
Explanation:
Many elements react with both acid and base and gives hydrogen gas and respective oxides. Such oxides are called amphoteric oxides.
Question (36) Which substances are produced in Yeast during fermentation?
| Lactic Acid | Carbon dioxide | Ethanol |
|---|---|---|
| (A) Yes | Yes | Yes |
| (B) Yes | No | No |
| (C) No | Yes | Yes |
| (D) No | No | Yes |
Which of the above option is correct?
(A) A
(B) B
(C) C
(D) D
Answer (C)
Explanation
Yeast produce carbon dioxide [CO2] and ethanol during fermentation.
Question (37) Lungs receive deoxygenated blood from the Heart through ____
(A) Pulmonary veins
(B) Pulmonary arteries
(C) Hepatic veins
(D) Hepatic arteries
Answer (B) Pulmonary arteries
Explanation
The deoxygenated blood is carried by pulmonary arteries to the lungs. And oxygenated blood is carried away from the lungs by Pulmonary veins.
Thus, the correct answer is option (B) Pulmonary arteries
Question (38) Name the part of Nephron where the capillaries cluster is present and that also collects the filtrate.
(A) Bowman's capsule
(B) Glomerulus
(C) Tubular part of nephron
(D) Collecting duct
Answer (A) Bowman's capsule
Explanation
Kidney is the part of excretory system in human beings. Kidney filters the waste products from the blood such as urea or uric acids. Kidney consists of many capillary cluster. These capillaries cluster in the kidney is associated with the cup shaped end of a coiled tube called Bowman's capsules that collect the filtrate.
Thus, the correct answer is option (A) Bowman's capsule
(39) The speed of light in a transparent medium is 0.6 times that of its speed in vacuum. What is the refractive index of the medium?
(A) 1.0
(B) 1.66
(C) 1.55
(D) 1.33
Answer (B) 1.66
Explanation
We know that, refractive index of a medium (2) with respect to the refractive index of medium (1)
Thus, refractive index of the given medium n(21)= 1/0.6 = 1.66
Thus, refractive index of the given medium = 1.66
Hence, the correct answer is option (B) 1.66
Question (40) A lens is able to produce magnification of both + 5 and – 5. Which statement is true w.r.t. the given condition?
(A) A concave lens when the object is placed at infinity and on principal axis respectively
(B) A concave lens when the object is placed between (i) O and f1 (ii) 2 f1 and f1
(C) A convex lens when the object is placed between (i) O and f1 and (ii) 2f1 and f1
(D) A convex lens when the object is placed between (i) 2f1 and f1, and (ii) O and f1
Answer (C) A convex lens when the object is placed between (i) O and f1 and (ii) 2f1 and f1
Explanation (C) A convex lens when the object is placed between (i) O and f1 and (ii) 2f1 and f1
Answer : (C) A convex lens when the object is placed between (i) O and f1 and (ii) 2f1 and f1
Explanation :
When object is placed between O and f1 in front of a convex lens a large image is formed beyond 2f1.
And when object is placed between 2f1 and f1 a small image is formed between f1 and O.
Thus, the correct answer is option (C) A convex lens when the object is placed between (i) O and f1 and (ii) 2f1 and f1