Q: To get an image, larger than object, one can use

A: Convex mirror

B: Concave mirror

C: Plane mirror

D: Plano Convex mirror



Correct Option: B  [ Concave mirror ]

Remark:

Explanation: A concave mirror can produce an image that is larger than the object when the object is placed between the mirror’s pole and its focal point. This property makes concave mirrors useful in applications like shaving mirrors and makeup mirrors, where magnified images are needed.


Q: All ships have sonar system. It is used to detect /measure :

A: Distance of the shore

B: Sound on the surface

C: Sound of animals in Sea

D: Depth of ocean



Correct Option: D  [ Depth of ocean ]

Remark:

Explanation: SONAR (Sound Navigation and Ranging) is a system used in ships and submarines to determine the depth of the ocean or to locate underwater objects. It works by sending sound waves into the water and measuring the time taken for the echo to return after reflecting from the seabed or any object.


Q: What is the temperature when density of water is the highest

A: 5 degree Celsius

B: 6 degree Celsius

C: 4 degree Celsius

D: 3 degree Celsius



Correct Option: C  [ 4 Degree Celsius ]

Remark:

Explanation: Water shows an unusual property known as anomalous expansion. Its density is maximum at 4°C. When cooled from higher temperatures, water contracts till 4°C, becoming denser. Below 4°C, it expands instead of contracting, so its density decreases. This property allows ice to float and prevents water bodies from freezing solid, protecting aquatic life during winters.


Q: What does the term Dolby B or Dolby C printed on tape recorders and other sound systems refer to?

A: frequency modulated system

B: amplitude modulated system

C: noise reduction circuit

D: both DC and AC power can be used



Correct Option: C  [ noise reduction circuit ]

Remark:

Explanation: The terms Dolby B and Dolby C refer to noise reduction circuits used in tape recorders and sound systems. These technologies reduce background hiss and unwanted noise during playback and recording, thereby improving the overall sound quality.


Q: Cause of global warming is:

A: Excessive use of organic manure

B: Increase in the amount of CO2 in the atmosphere

C: Increase in the amount of atmospheric nitrogen

D: Excessive use of fertilizer.



Correct Option: B  [ Increase in the amount of CO2 in the atmosphere ]

Remark:

Explanation: The main cause of global warming is the rise in the concentration of carbon dioxide (CO₂) and other greenhouse gases in the atmosphere. These gases trap heat radiated from the Earth’s surface, creating the greenhouse effect and leading to an overall increase in the planet’s temperature.


Q: The pale yellow colour of urine is due to the presence of which pigment?

A: Urophyll

B: Urochrome

C: Chlorophyll

D: Chloroplast



Correct Option: B  [ Urochrome ]

Remark:

The pale yellow colour of urine is due to the presence of the pigment Urochrome. Urochrome is a waste product formed from the breakdown of hemoglobin in red blood cells. It is produced when hemoglobin is metabolized into urobilin and then excreted through urine. The intensity of the yellow color can vary depending on hydration levels — darker urine indicates dehydration, while pale urine indicates proper hydration.

Other options (for context)

  • Urophyll: No such pigment exists in human physiology.
  • Chlorophyll: Green pigment found in plants, not in urine.
  • Chloroplast: Cell organelle in plants where photosynthesis occurs, not a pigment.


Q: The moon takes __________ days to go round the earth once.

A: 28 days

B: 45 days

C: 50 days

D: 65 days



Correct Option: A  [ 28 days ]

Remark:

The Moon takes about 27.3 days to complete one revolution around the Earth with respect to the stars (called the sidereal month). However, due to the simultaneous movement of the Earth around the Sun, the Moon takes approximately 29.5 days to complete one full cycle of phases (from new moon to new moon), known as the synodic month. This period is commonly rounded to 28 days in general usage.

Other options (for context)

  • 45 days: Much longer than the Moon’s actual orbital period.
  • 50 days: Incorrect — the Moon completes more than one revolution in this time.
  • 65 days: Far too long compared to the real lunar cycle.


Q: All biological reaction in a living organism come under

A: Anabolism

B: Catabolism

C: Metabolism

D: Metamorphosis



Correct Option: C  [ Metabolism ]

Remark:
"Metabolism" involves two main categories of reactions:
1.Catabolism: This is the breakdown of larger molecules into smaller ones.

2. Anabolism: This is the synthesis of larger molecules from smaller ones.


Q: Adult Filaria worms live in human:

A: Blood

B: Lymphatics

C: Liver

D: Intestine



Correct Option: B  [ Lymphatics ]

Remark:

Explanation: The adult filarial worm, Wuchereria bancrofti (and Brugia malayi), lives in the lymphatic vessels and lymph nodes of humans. These worms block the lymphatic system, causing a condition known as lymphatic filariasis or elephantiasis, characterized by severe swelling of legs, arms, or genitals. The disease is transmitted by the bite of infected Culex mosquitoes, which carry t


Q: What is Air Quality Index ?

A: It tells about sound pollution.

B: It measures air pollution mainly sulphur content in the air.

C: It measures ozone levels in the selected area.

D: It checks the colour of the air.



Correct Option: C  [ It measures ozone levels in the selected area. ]

Remark:

The Air Quality Index (AQI) is a numerical scale used to measure and report the quality of air in a particular area. It primarily indicates the level of air pollution and its potential impact on human health. The AQI is calculated based on concentrations of key air pollutants — including ozone (O₃), particulate matter (PM₂.₅ and PM₁₀), nitrogen dioxide (NO₂), sulphur dioxide (SO₂), and carbon monoxide (CO). Higher AQI values indicate poorer air quality and greater health risks.

Other options (for context)

  • It tells about sound pollution: Incorrect — AQI is unrelated to noise levels.
  • It measures air pollution mainly sulphur content in the air: Partly true, but AQI includes multiple pollutants, not just sulphur dioxide.
  • It checks the colour of the air: Inc
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