Lakhmir Singh and Manjit Kaur Solutions for Chapter: Model Test Paper (As Per the Latest Marking Scheme), Exercise 1: MODEL TEST PAPER (As per the latest marking scheme)

Which postulate of Dalton's atomic theory can explain the law of conservation of mass?

Find the momentum of a body of mass $100 \mathrm{g}$ having a kinetic energy of $20 \mathrm{J}$.

Why cannot a sound be heard on the moon? How do astronauts talk to one another on the surface of moon?

Discuss why the pesticides are used in very accurate concentration and at a very appropriate time?

Draw a neat diagram of plant cell and label any three parts which differentiate it from an animal cell.

Why a person suffering from AIDS cannot fight even minor infections?

When $5 \mathrm{g}$ of calcium is burnt in $2 \mathrm{g}$ of oxygen, then $7 \mathrm{g}$ of calcium oxide is produced. What mass of calcium oxide will be produced when $5 \mathrm{g}$ of calcium is burnt in $20 \mathrm{g}$ of oxygen?  Which law of chemical combination will govern your answer.

A stone and the earth attract each other with an equal and opposite force. Why then we see only the stone falling towards the earth but not the earth rising towards the stone?