Plus 2 Lecturer Mixed Practice Test #925

Question 1

A rainbow is formed by:‌​‍

Accepted Answer

Refraction, dispersion and total internal reflection in water droplets — Sunlight refracts entering droplet, disperses, undergoes internal reflection, refracts again on exit.‌​‍

Answer

Refraction only

Answer

Reflection only

Answer

Diffraction

Question 2

Resolution of a measurement is:‌​‍

Accepted Answer

Least count — smallest change detectable — Vernier caliper LC = 0.01 cm; screw gauge 0.001 cm. ‌​‍Measurement reported to least count precision.

Answer

Maximum value

Answer

Mean

Answer

Error

Question 3

UNCCD:‌​‍

Accepted Answer

UN Convention to Combat Desertification — 1994 treaty.‌​‍

Answer

UN Customs

Answer

UN Conservation

Answer

UN Climate

Question 4

The speed of light in glass (n=1.5) compared to vacuum is:

Accepted Answer

1.5 times slower — v = c/n = 3×10⁸/1.5 = 2×10⁸ m/s.

Answer

Same

Answer

1.5 times faster

Answer

Zero

Question 5

Who founded the Nair Service Society (NSS)?‌​‍

Accepted Answer

Mannathu Padmanabhan — Mannathu Padmanabhan founded the Nair Service Society (NSS) in 1914 for the social and educational upliftment of the Nair community.‌​‍

Answer

K. Kelappan

Answer

C. Kesavan

Answer

T.K. Madhavan

Question 6

The chemical formula of washing soda is:‌​‍

Accepted Answer

Na₂CO₃ — Washing soda = Sodium Carbonate (Na₂CO₃). ‌​‍Baking soda = NaHCO₃. Common salt = NaCl.

Answer

NaCl

Answer

NaHCO₃

Answer

CaCO₃

Question 7

A uniform circular disc of radius 0.5 m and mass 3 kg is rotating about its central axis with an angular velocity of 10 rad/s. If the radius is increased to 0.75 m without changing the mass distribution, what will be the new angular velocity? (Assume conservation of angular momentum)

Accepted Answer

A. 4.44 rad/s — Angular momentum L = Iω is conserved. For a disc, I = ½mr², so ω₂ = (I₁/I₂) * ω₁ = (r₁²/r₂²) * ω₁ = (0.5²/0.75²) * 10 ≈ 4.44 rad/s. Option A (4.44 rad/s) is correct. Option B (6.67 rad/s) results from using diameter instead of radius. Option C (10.00 rad/s) assumes no change. Option D (15.00 rad/s) is a miscalculation of the ratio.

Answer

B. 6.67 rad/s

Answer

C. 10.00 rad/s

Answer

D. 15.00 rad/s

Question 8

Study of inscriptions:

Accepted Answer

Epigraphy — Epigraphy.

Answer

Numismatics

Answer

Philately

Answer

Calligraphy

Question 9

Deepest lake world:

Accepted Answer

Baikal — Baikal (1,642m).

Answer

Tanganyika

Answer

Caspian

Answer

Superior

Question 10

Arabian Sea cyclone Tauktae Kerala:

Accepted Answer

May 2021 — Severe cyclone near Kerala coast.

Answer

2020

Answer

2019

Answer

2022

Plus 2 Lecturer Mixed Practice Test #925