Clouds float in atmosphere because of their low

(a)

density

(b)

pressure

(c)

velocity

(d)

mass

The speeds of sound in four different media are given below. Which of the following is the most likely speed in ms^-1 with which the two underwater whales in a sea can talk to each other when separated by a large distance?

(a)

5170

(b)

1280

(c)

340

(d)

1530

Ceres is a _______.

(a)

Meteor

(b)

Star

(c)

Planet

(d)

Astroid

A phenomenon in which an element exists in different modification in same physical state is called

(a)

Isomerism

(b)

Allotropy

(c)

Catenation

(d)

Crystallinity

Diamond is not a good conductor of electricity because

(a)

it is very hard

(b)

it has no free electron

(c)

its structure is uniform

(d)

it is insoluble in water

Chlorinated hydrocarbons are used as

(a)

fertilizers

(b)

pesticides

(c)

food colourants

(d)

preservatives

Which of the following is not an adaptation of hydrophytes?

(a)

poorly developed root system

(b)

reduced plant body

(c)

water storing parenchymatous tissues

(d)

finely divided submerged leaves

Binomial name of Nilavembu is

(a)

Leucas aspera

(b)

Andrographis paniculata

(c)

Crotolaria juncea

(d)

Cassia fistula

The major constituent of vinegar is

(a)

citric acid

(b)

acetic acid

(c)

oxalic acid

(d)

hydrochloric acid

_________is an Operating System.

(a)

Android

(b)

Chrome

(c)

Internet

(d)

Pendrive

Define orbital velocity.

Define time period of a satellite.

How many valence electrons are there in carbon?

What is the need for chemical fertilizers in crop fields?

Define Compost

Differentiate Pollen and Nectar

Assertion: To float, body must displace liquid whose weight is equal to the actual weight.
Reason: The body will experience no net downward force in that case.
(a) If both assertion and reason are true and reason is the correct explanation of assertion.
(b) If both assertion and reason are true but reason is not the correct explanation of assertion.
(c ) If assertion is true but reason is false.
(d) If assertion is false but reason is true.

Assertion: Wide wooden sleepers are kept below railway lines to reduce pressure on the railway tracks and prevent them from sinking in the ground.
Reason: Pressure is directly proportional to the area in which it is acting.
(a) If both assertion and reason are true and reason is the correct explanation of assertion.
(b) If both assertion and reason are true but reason is not the correct explanation of assertion.
(c) If assertion is true but reason is false.
(d) If assertion is false but reason is true.

On what factors the pressure exerted by the liquid depends on?

Why does a helium balloon float in air?

Through which medium sound travels faster, iron or water? Give reason.

Can sound travel through vacuum?

Write about comets.

Carbon do not form ionic compounds. Why?

What is IUCN? What is the vision of IUCN?

Mention any two mushroom preservation methods.

A baby is suffering from diarrhoea, while other babies in the same locality do not. Mention the possible causes that you think. What would be the possible solutions for this?

1. Why does a boat with a hole in the bottom would eventually sink?

2. Verify experimentally the laws reflection of sound.

1. Write a note on orbital velocity.

2. Why do carbon exist mostly in combined state?

1. Draw the cell diagram of Daniel cell. Give its reactions.

2. What is water recycling? Explain the conventional wastewater recycling treatment methods?

1. Write short notes on;
   a) Importance of green houses
   b) Uzahavan mobile Application
   c) Major floriculture zones
   d) Azospirillum

2. Name the causative agent of typhoid in human. How does the pathogen gain entry into the human body? Write the diagnostic symptoms and mention the organ that is affected in severe cases.