Show:
PHYSICS
CHEMISTRY
BIOLOGY
GENERAL SCIENCE
100

The picture of four people pushing four heavy boxes of equal weight on a surface in four different situations I, II, III, and IV respectively, is shown in the given figure.

The maximum and the minimum friction offered by the ground will be for the situations.

I and II

III and IV


II and III

I and IV

III and IV

100
  1. In which of the given case we can use water as a fire extinguisher?

a) Fire due to burning of wood or paper

b) Fire due to short circuit

c) Fire due to burning of oil and petrol

d) All of the above

a) Fire due to burning of wood or paper

100
  • Which of the following statements best explains the role of nitrogen-fixing bacteria in agriculture?a) They directly provide nitrogen in the form of ammonia to plants, enhancing their growth.        b) They convert atmospheric nitrogen into nitrates, which plants absorb for protein synthesis.                                                            c) They convert nitrogen gas directly into organic matter, enriching soil nutrients.
  • d) They break down complex nitrogen compounds in dead organisms, replenishing soil nitrogen.

 b) They convert atmospheric nitrogen into nitrates, which plants absorb for protein synthesis. 

Explanation:

Nitrogen-fixing bacteria (e.g., Rhizobium) fix atmospheric nitrogen and convert it into usable forms such as nitrates. These nitrates are then absorbed by plants through their roots and used to synthesize proteins. This understanding allows students to conclude that nitrogen-fixing bacteria play a crucial role in agriculture by making nitrogen available for plant growth.

100

1. Decibel is the unit of _______.

A. Speed of light

B. Intensity of sound

C. Intensity of heat

D. None of these

B. Intensity of sound

200

Q2. A magnet can pull an iron nail toward itself. The maximum distance from which the magnet (shown in the given figure) can pull the nail is labelled as d.

On which surface will this distance d be relatively large?

1.         Cemented surface.

2.         Carpeted surface.

3.         Sandy surface.

4.         Oily surface.

Oily surface.

200

Which of the given options is correct for A, B, C and D respectively?

a) Oil, gas, water, rock

b) Gas, water, Oil, Impervious rock

c) Water, oil, gas, Impervious rock

d) Impervious rock, oil, gas, water

c) Water, oil, gas, Impervious rock

200

Why might antibiotics become less effective if overused?

  • a) Microorganisms can evolve mechanisms to degrade the antibiotics.
  • b) Antibiotics become weaker over time due to their chemical composition breaking down.
  • c) Overuse of antibiotics leads to an increase in helpful bacteria, reducing the impact of treatment.
  • d) The human immune system becomes reliant on antibiotics, lowering its natural defense mechanisms.
  • a) Microorganisms can evolve mechanisms to degrade the antibiotics.

Explanation:

The chapter, MICROORGANISMS: FRIEND AND FOE, discusses the importance of using antibiotics correctly and warns against overuse. It indicates that improper use can lead to the development of resistant strains of bacteria. Contestants are expected to infer that bacteria may evolve to survive despite antibiotic treatment, making the drugs less effective.

200

2.Radio waves, microwaves, infra-red spectrum, ultraviolet rays, X-rays and gamma rays are classified as __________.

 A. light waves

B. electromagnetic waves

C. electric waves

D. magnetic waves

B. electromagnetic waves

300

Q3. A brick is kept in three different ways on a table as shown in Figure The pressure exerted by the brick on the table will be:

  • Maximum in position A.
  • Maximum in position C.
  • Maximum in position B.
  • Equal in all cases.
  • Maximum in position A.
300

Which of the following is not a part of incomplete combustion?

A) Carbon dioxide

B) Heat

C) Carbon monoxide

D) Oxygen

A) Carbon dioxide

300

Which of the following scenarios would most likely lead to the emergence of antibiotic-resistant bacterial strains?

  • a) A community regularly using antibiotics to treat viral infections.
  • b) A person completing the full prescribed course of antibiotics even after symptoms subside.
  • c) A healthcare system providing vaccination programs alongside antibiotic treatments.
  • d)Using antibiotics as a preventive measure in livestock feed to promote growth.
  • d) Using antibiotics as a preventive measure in livestock feed to promote growth.

Explanation:

Using antibiotics in livestock can promote growth and prevent infections. This continuous exposure to antibiotics leads to the development of antibiotic-resistant bacteria. Contestants are expected to connect the concept of antibiotic use in animals with the potential consequences of bacterial resistance.

300

Who gave the basis of Modern Periodic Table?

a) Dobereiner

b) Moseley

c) Lavoisier

d) Dalton

b) Moseley

400

A block of mass 10kg is suspended through two light spring balances as shown in figure. Then:

  • Both the scales will read 10kg.
  • Both the scales will read 5kg.
  • The upper scale will read 10kg and the lower scale zero.
  • The reading may be anything but their sum will be 10kg.
  • Both the scales will read 10kg.
400

What will you choose to cease the fire if there is a short circuit in a house?

A) Water

B) Blanket

C) Carbon dioxide

D) Sand

C) Carbon dioxide

400

Deforestation is known to cause both droughts and floods. What is the underlying reason for this paradox?

  • a) Deforestation reduces atmospheric carbon dioxide, impacting cloud formation.
  • b) The loss of trees decreases water absorption by the soil, leading to runoff and soil erosion.
  • c) It causes erratic weather patterns by disturbing the Earth's gravitational field.
  • d) The reduction in photosynthesis creates a surplus of oxygen, altering water distribution cycles.
  • b) The loss of trees decreases water absorption by the soil, leading to runoff and soil erosion.

Explanation:

Trees prevent soil erosion and help maintain water retention in the soil. Without trees, the soil loses its ability to absorb water, leading to both increased runoff (causing floods) and reduced moisture retention (causing droughts). Contestants are expected to understand that deforestation disrupts the water cycle, causing these extreme weather conditions.

400

What is the melting point of Hg (Mercury)?

a) -40 degrees

b) 40 degrees

c) 100 degrees

d) 0 degrees

a) -40 degrees

500

Q5. In the curve (Fig.) half the wavelength is:

  • AB
  • BD
  • DE
  • AE
  • AE
500

For the below reaction 

H2 + O2 --> H2O

The coefficient of water in the balanced equation is:

2

500

Which of the following best describes the role of biosphere reserves in conservation?

  • a) They exclusively focus on protecting animal species from extinction.
  • b) They integrate conservation of biodiversity with the sustainable use of natural resources by humans.
  • c) They act as isolated ecosystems that prevent human interaction with natural habitats.
  • d) They serve as tourism spots to raise funds for wildlife conservation efforts.

b) They integrate conservation of biodiversity with the sustainable use of natural resources by humans.

Explanation:

Biosphere reserves are the areas that conserve biodiversity while allowing for sustainable human activities, such as collecting medicinal plants. This dual function emphasizes the importance of balancing conservation with human needs. Contestants are expected to infer that biosphere reserves are designed to protect both the environment and human livelihoods.

500

What is the scientific name of Cockroach?

periplaneta americana