Q&A: practice questions with answers

Concept: Decode each symbol and link the chain.

1. G + H: G is the mother of H; H ÷ I: H is the daughter of I → I (male) is H's father, so G is I's wife.
2. I − J: I is the brother of J; J × K: J is the sister of K → I is K's brother.
3. G = wife of K's brother.

Yaad rakhein: Mother of a child + father of the same child ⇒ husband–wife.

Answer: (C) Brother's wife

Concept: Track coordinates: north +y, east +x.

1. 9 N → (0, 9); left 8 W → (−8, 9); left 13 S → (−8, −4).
2. Left 11 E → (3, −4); left 4 N → (3, 0) = P.
3. P is 3 km east of A → drive 3 km west.

Trick: Net N–S: 9 − 13 + 4 = 0; net E–W: 11 − 8 = 3 E. So go back 3 km west.

Answer: (C) 3 km to the west

Concept: Find the shift for each letter position.

1. WAVE → XBXG: +1, +1, +2, +2.
2. KING → LJPI: +1, +1, +2, +2.
3. SONG → S+1 = T, O+1 = P, N+2 = P, G+2 = I → TPPI.

Trick: S+1 = T eliminates RPOI and RRPK; O+1 = P picks TPPI.

Answer: (C) TPPI

Concept: Find the shift of each letter.

1. IRQ → KPP: +2, −2, −1; MEU → OCT: +2, −2, −1.
2. RQN → TOM: +2, −2, −1 ✓.
3. GRP→IPN and CMR→EKP have −2 at the end; FJM→HGL has −3 in the middle.

Trick: First letters all +2, so check only the 2nd and 3rd shifts (−2, −1).

Answer: (C) RQN : TOM

Concept: Position from left = total − position from right + 1.

1. Karan from left = 29 − 9 + 1 = 21st.
2. Ramesh is 5th to his left → 21 − 5 = 16th.

Yaad rakhein: Always convert both positions to the same end before adding or subtracting.

Answer: (D) 16th

Concept: Perfect-square digits: 1, 4, 9; look at the digit right after each and its next neighbour.

1. After a square: 1→4 (next 8 ✗), 4→8 (next 7 ✓), 1→3 (next 7 ✓).
2. 4→8 (next 9 ✓), 9→5 (next 4 ✗), 4→3 (next 5 ✓).
3. Valid digits: 8, 3, 8, 3 → four.

Trick: Underline every 1, 4, 9 first; then just check the digit two places ahead for oddness.

Answer: (B) Four

Concept: Replace letters by signs, then apply BODMAS.

1. $2\times 1-14÷2+7$.
2. $=2-7+7$.
3. $=2$.

Yaad rakhein: Division and multiplication first, then addition and subtraction from left to right.

Answer: (D) 2

Concept: Link the chain from Piyush to Abhimanyu.

1. Piyush is the brother of Vidhi, and Vidhi is the sister of Kunti → Piyush is Kunti's brother.
2. Kunti is Arjun's wife, Arjun is Abhimanyu's father → Kunti is his mother.
3. Piyush = mother's brother (maternal uncle).

Yaad rakhein: Wife of the father = mother (unless stated as step-mother).

Answer: (C) Mother's brother

Concept: Locate vowels (A, E, I, O, U) and check both neighbours.

1. Z I U → I: preceded by consonant Z, followed by vowel U ✓.
2. X O E → O ✓; B E A → E ✓.
3. U, E (after O) and A fail (preceded by a vowel) → three.

Trick: Look only for two vowels side by side; the first of the pair counts if a consonant stands before it.

Answer: (A) Three

Concept: Sort the word, pick the letters, count letters between them.

1. EDITORIAL sorted: A D E I I L O R T.
2. 4th from left = I; 2nd from right = R.
3. Between I (9) and R (18): 18 − 9 − 1 = 8 (J to Q).

Trick: Letters between = difference of positions − 1.

Answer: (A) 8

Concept: $F=\frac{G·m_1{m}_2}{r^2}$: force ∝ product of masses and $\propto \frac{1}{(\text{distance}{)}^2}$.

1. More mass → more force; more distance → much less force (inverse square).
2. Options A, C, D contradict $F\propto \frac{m_1{m}_2}{r^2}$.

Yaad rakhein: $G=6.67\times {10}^{-11}{\text{N m}}^2{\text{kg}}^{-2}$; the law was given by Newton.

Answer: (B) The gravitational force increases with the product of the masses and decreases with the square of the distance between them.

Concept: $F\propto \frac{1}{r^2}$.

1. Distance doubled: $r\to 2r$.
2. $F^{\prime }=\frac{F}{(2{)}^2}=\frac{F}{4}$.

Trick: Distance × n → force $÷n^2$.

Answer: (D) F/4

Concept: Take the direction of initial (upward) motion as positive.

1. Gravity acts downward, opposite to the upward velocity.
2. So $a=-g=-9.8{\text{m/s}}^2$; the body slows down while rising.

Yaad rakhein: At the highest point $v=0$, and max height $h=\frac{u^2}{2g}$.

Answer: (C) Negative, as it opposes the initial motion.

Concept: Tall columnar cells line places of absorption and secretion.

1. Inner lining of the intestine = simple columnar epithelium (with microvilli) for absorption.
2. Squamous lines blood vessels/alveoli; cuboidal lines kidney tubules and gland ducts.

Yaad rakhein: Columnar epithelium with cilia (ciliated) lines the respiratory tract.

Answer: (D) Simple columnar epithelium

Concept: Connective tissue binds, supports and connects other tissues.

1. Bone, cartilage, ligament, tendon give framework and support.
2. Contraction = muscle; impulses = nerve; absorption = epithelium.

Yaad rakhein: Blood is a fluid connective tissue (matrix = plasma).

Answer: (D) Supporting and providing structural framework to body parts.

Concept: Constant velocity → v does not change with t.

1. v–t graph is a horizontal line parallel to the time (x) axis.
2. Slope = acceleration = 0; area under graph = displacement.

Yaad rakhein: A straight line through the origin on a v–t graph means uniform acceleration from rest.

Answer: (B) Straight line parallel to the x-axis

Concept: Sound obeys the laws of reflection like light.

1. Curved ceilings and sound boards reflect sound so it spreads evenly across the hall.
2. They do not absorb or block sound; absorbing materials are used separately to reduce reverberation.

Yaad rakhein: Megaphones, stethoscope and ear trumpets also work by multiple reflection of sound.

Answer: (D) To reflect sound evenly

Concept: Successive members differ by –CH₂–.

1. Statement 1 is true.
2. Mass of CH₂ = $12+2\times 1=14$ u, not 12 u → Statement 2 is false.

Yaad rakhein: Members of a homologous series have the same functional group and similar chemical properties.

Answer: (D) Statement 1 is true but Statement 2 is false.

Concept: A compound always has elements in a fixed mass ratio (H : O = 1 : 8 in water).

1. $36\text{ g}=4\times 9\text{ g}$.
2. Hydrogen = $4\times 1=4$ g; oxygen = $4\times 8=32$ g.

Trick: Check the sum: $4+32=36$ – only option A adds up to 36 g.

Answer: (A) 4 g of hydrogen and 32 g of oxygen

Concept: Non-biodegradable chemicals are not broken down or excreted, so they build up along the food chain.

1. Concentration increases at each successive trophic level.
2. Humans at the top get the highest dose even from small pesticide use.

Yaad rakhein: DDT is the classic example of biomagnification.

Answer: (C) Non-biodegradable pesticides accumulate at successive trophic levels