Some countries now use alcohol as an additive in petrol. In context of this, consider the following statements:
1. Addition of alcohol increases the burning efficiency of petrol and reduces knocking.
2. Petrol added with small quantities of alcohol becomes more stable and doesn’t become too hot in warm areas or too cold in freezing temperatures.
3. Alcohol is a cleaner fuel which gives rise to only carbon dioxide and water on burning in sufficient oxygen.
Which of the statements given above is the correct reason for using alcohol as an additive in petrol?
More Questions Selected Just For You. Attempt Now!
With reference to the uses of ‘concave mirrors’, read the following statements carefully:
1. They are commonly used in vehicles headlights to get powerful parallel beams of light.
2. They are often used as shaving mirrors to see a larger image of the face.
3. They are fitted on the sides of the vehicle to have a wider field of view.
4. Large concave mirrors are used to concentrate sunlight to produce heat in solar furnaces.
Which of the statements given above is/are correct?
Consider the following statements with reference to the ‘magnetic field’ of a bar magnet:
1. Magnetic field is a quantity that has both direction and magnitude.
2. Inside the magnet, the direction of field lines is from its south pole to north pole.
3. Magnetic field-lines of two different magnets can intersect each other.
Which of the statement(s) given above is/are correct?
Some countries now use alcohol as an additive in petrol. In context of this, consider the following statements:
1. Addition of alcohol increases the burning efficiency of petrol and reduces knocking.
2. Petrol added with small quantities of alcohol becomes more stable and doesn’t become too hot in warm areas or too cold in freezing temperatures.
3. Alcohol is a cleaner fuel which gives rise to only carbon dioxide and water on burning in sufficient oxygen.
Which of the statements given above is the correct reason for using alcohol as an additive in petrol?
Match the following pairs with reference to different types of ‘Phyla’ with their most distinctive features:
PHYLA | MOST DISTINCTIVE FEATURE |
1. Ctenophora | A. Body segmentation like rings. |
2. Platyhelminthes | B. Comb plates for locomotion. |
3. Annelida | C. Presence of jointed appendages. |
4. Arthropoda | D. Flat body, suckers |
Select the correct answer using the code given below.
According to Archimedes’ principle - When a body is immersed fully or partially in a fluid, it experiences an upward force that is equal to the weight of the fluid displaced by it. Which among the following are based on the application of this principle?
1. Ships
2. Lactometer
3. Thermometer
Select the correct answer using the code given below:
Weeds are unwanted plants in a cultivated field. In this context, consider the following statements:
1. The weeds compete for food, space and light.
2. Weeds are responsible for affecting the growth of the crop.
3. Timely sowing of crops and crop rotation help in weed control.
Which of the statement(s) given above is/are correct?
Consider the following statements about Carbon dioxide (CO2):
1. Volcanic eruptions are a natural source of Carbon dioxide in the atmosphere.
2. Carbon dioxide is confined only to the tropospheric layer of the atmosphere.
3. Excess of Carbon dioxide in the air is removed by green plants by respiration.
Which of the statements given above is/are correct?
In context of Air pollution in India, consider the following statements:
1. Presence of high levels of pollutants in air causes visibility to be lowered.
2. Formation of smog is a visible indication of air pollution.
3. Oxides of nitrogen and sulphur dissolve in rain to give rise to acid rain.
Which of the statement(s) given above is/are correct?
Consider the following statements about ‘Acid Rain’:
1. Oxides of sulphur and nitrogen are major contributors to acid rain.
2. Acid rain is good for agriculture as it provides nitrogen for the growth of plants.
3. When acid rain flows into the river, it increases the pH level of river water.
Which of the statements given above is/are correct?
Consider the following statements about the ‘scattering of light’:
1. Very fine particles scatter mainly blue light while particles of larger size scatter light of longer wavelengths.
2. If the size of the scattering particles is large enough, then, the scattered light may even appear white.
Which of the statements given above is/are correct?