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What is Periscope?

Posted by Asbwani Kumar Sharma 8 years, 2 months ago

CBSE > Class 08 > Science

0 answers

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When does puberty end

Posted by Swathi Krishna Kumar 8 years, 2 months ago

CBSE > Class 08 > Science

2 answers

Shruti Dadhwal 8 years, 2 months ago

Puberty age is from 11to 19 years.

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Manvi Singh 8 years, 2 months ago

Normally In girls it end at the age of 15 whereas in boys it end at the age of 16 . However it may vary from person to person

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What is a flame?explain the structure of a flame

Posted by Govardhan Subudhi 8 years, 2 months ago

CBSE > Class 08 > Science

1 answers

Amar Kumar 8 years, 2 months ago

A flame (from Latin flamma) is the visible, gaseous part of a fire. It is caused by a highly exothermic reaction taking place in a thin zone.

A flame consist of three zones.These are Innermost zone,middle zone,outer zone.The three zones of a flame have different colours and different temperature.

1) The Innermost zone of a flame is dark or black:It consist of hot,unburnt vapours of the combustible material.It is the least hot part of the flame.It is the coldest part of the flame.

2)The middle zone of a flame is yellow:It is bright and luminous.The fuel vapours burn partially in the middle zone because there is not enough air of burning in this zone.The partial burning of fuel in the middle zone produces carbon particles.These carbon particles then leave the flame as smoke and soot.It has moderate temperature.

3)The outer zone of a flame is blue:It is a non-luminous zone.In this zone,complete combustion of the fuel takes place because there is plenty of air around it.The outermost zone has the highest temperature in the flame.It is the hottest part of the flame.It is quite thin as compared to middle zone.

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What is interlocking

Posted by Shivani Rana 8 years, 2 months ago

CBSE > Class 08 > Science

0 answers

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What is thelarche?

Posted by Nikhil Kumar 8 years, 2 months ago

CBSE > Class 08 > Science

0 answers

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What is force define the types of force in detail

Posted by Saifu Deen 8 years, 2 months ago

CBSE > Class 08 > Science

1 answers

Amar Kumar 8 years, 2 months ago

A force is a push or pull acting upon an object as a result of its interaction with another object.

Types of forces:-

Contact Force :Forces which act on a body either directly or through a medium are called contact forces. The examples of contact forces are a Muscular force, mechanical force and Frictional Force. We can make use of muscular force of animals like bullocks, horses and camels to get the activities done. The frictional force is another type of contact force which acts between a pair of a surface in contact and tends to oppose the motion of one surface over the other.

Non-Contact Force :Forces which act through spaces without making direct contact with the body are called non-contact forces. The examples of non-contact forces are the Gravitational force, electrostatic force and magnetic force. The force exerted by a magnet on other magnets is called magnetic force. Magnetic force and electrostatic force act on an object from a distance, that’s the reason they are non-contact forces. The strength of gravity is an attractive force which is exerted by the Earth on objects which make them fall to the land. The weight of a body is the force which is pulled by the earth towards the centre.

The magnitude of the force is given by the product of the mass of the object (m) and its acceleration (a).

F = ma

Contact Forces are Frictional Force , Tension Force, Normal Force, Air Resistance Force, Applied Force, Spring Force.

Non-Contact Forces are Gravitational Force, Electrical Force, Magnetic Force.

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What is sond

Posted by Jatin Chauhan 8 years, 2 months ago

CBSE > Class 08 > Science

0 answers

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What is cause friction

Posted by Divya Kumari 8 years, 2 months ago

CBSE > Class 08 > Science

1 answers

Amar Kumar 8 years, 2 months ago

When we try to move one object over another object, the irregularities present on their surface get entangled or locked with one another. The interlocking of irregularities of the two surfaces opposes the motion of one object over the other and give rise to force of friction.

Friction is caused by the interlocking of irregularities in the surface of two objects which are in contact with each other. To move one object over the other ,we have to apply a force to overcome interlocking of the irregularities in their surfaces.

More the roughness of a surface larger is the number of irregularities on its surface and has greater will be the friction does the force of friction.

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