Which one of the following is not a conductor of electricity?

• Saltwater

• Distilled water

• Vinegar

• Lime juice

Medium A is optically denser than Medium B. Which one of the following statements is true?

• Speed of light is same in both A and B

• Cannot be compared

• Speed of light is more in medium A than in medium B

• Speed of light is more in medium B than in medium A

We are not crushed under the weight of the atmosphere, because

• the pressure inside our body is less than atmospheric pressure

• the pressure inside our body is equal to the atmospheric pressure and cancels the pressure from outside

• the pressure inside our body is more than atmospheric pressure

• the pressure inside our body is more than atmospheric pressure and cancels the pressure from outside

A block of iron dropped in a vessel of water, sinks to the bottom. This is because

• the weight of the block is less than the weight of the water displaced by the block

• the density of water is more than the density of the block

• the vessel is not deep enough to allow the block to float

• the weight of the water displaced by the block is less the weight of the block

Which one of the following statements is incorrect?

• Generally, the voice of a man is shriller than that of a woman

• A bird makes a high pitched sound whereas a lion makes a low pitched roar

• A drum vibrates with a low frequency, therefore it produces a low pitched sound

• A whistle has a high frequency and therefore it produces a sound of higher pitch

There are two planets in our solar system which rotate from East to West. These planets are

• Mercury and Venus

• Uranus and Neptune

• Mercury and Uranus

• Venus and Uranus

The major excretory product in human beings is

• uric acid

• ammonium chloride

• urea

• ammonia

Which of the following process/processes destroy/destroys the magnetic properties of a bar magnet?

1. Cutting into two pieces
2. Heating
3. Beating
4. Sealing

• I, II and III

• I and IV

• Only I

• II and III

9.

A VIIIth class student makes the statement.

"Heavy objects sink in water and light objects float."

How is the science teacher of the VIII class best advised to react?

• Present counter examples and arrange materials of different shapes, sizes and weights for the child to investigate

• Explain that heavy and light are relative terms

• Accept the statement as it indicates the child's ideas and needs to be respected

• Explain to the child that it is not the weight but the density of an object that determines whether it is going to sink or float

Which one among the following situations gives the students, the best opportunity of 'discovery learning'?

• Encouraging students to investigate factors affecting germination through experimentation

• Instructing students through team teaching on the topic of 'components of food'

• Students being first shown the demonstration of germination of seed followed by a detailed explanation

• Elaborated and detailed session of programmed instruction on the topic of 'germination of seed'