Give scientific reasons for the following:
Dust and other small particles are attached by a plastic comb which has been moved vigorously through dry hair.

Give scientific reasons for the following: Common salt has high melting and boiling points .

Give scientific reasons for the following: Air is bubbled through the mixture in froth floatation process

Give scientific reason: Darwin's work on evolution has been a milestone.

Give the scientific reason: The albino person has pale skin and white hair.

Give scientific reasons: In plants like Touch-me-not (Mimosa), movement also occurs at the places other than where it has been touched.

Answer the following : In the figure alongside , a string , attached to a wooden block on a table , is passed over a pully and tied to a weight . On applying a sufficient weight, the block will be seen to move : If the block moves forward we can say that it has been displaced . due to the displacement , we sat that the force has done some work . can we measure this work ?:

Read the given passage and answer the following questions: The home electrical connection consists of 'live','neutral' and 'earth wires. The 'live' and the 'neutral' wires have potential difference of 220 v. The earth ire is connected to ground. Due to a fault in the equipment or if the plastic coating on the 'live ' and the neutral wires gives away the two wires come in contact with each other and a large current flows through it producing heat . If any inflammable material (such as wood , cloth , plastic etc). exists around that place it can catch fire. Therefore a fuse wire is used as a precautionary measures. Name the two wires having potential difference of 220 v.