NCERT Solutions for Chapter: Force and Pressure, Exercise 1: Exercise

Give reason for the following statement.

Flat and broad feet of a camel help it walk on sand with ease.

Give a reason for the following statement.

Pieces of paper bits are attracted towards a plastic comb rubbed on the dry hair.

How would the pressure (exerted by a force on an area) change if the area is doubled keeping the thrust constant?

$\text{'}P\text{'}$ amount of lateral pressure is applied on either sides of a cuboidal dough horizontally. The length of the dough is reduced to half resulting change only in the height, then find the pressure applied by the dough at the bottom of it.

A bunch of five identical balloons can lift a toy of weight $100 \mathrm{N}$. Find out the pressure inside a single balloon to do this, if the radius of the balloon is $\frac{1}{\sqrt{\mathrm{\pi }}} \mathrm{m}$.

Express $4 \mathrm{newton}$ in terms of $\mathrm{g} \mathrm{cm} {\mathrm{s}}^2$.

The height of mercury column on a barometer at sea level is $76 \mathrm{cm}$ and that at a particular height is $63.3 \mathrm{cm}$. Calculate the height from the sea level(for every $272.7 \mathrm{m}$ of height from the sea level $2.54 \mathrm{cm}$ of pressure decreases).

A silver cube of base area of $30 {\mathrm{m}}^2$and mass $2 \mathrm{kg}$ is melted and changed into a cuboid of area of cross section $2 {\mathrm{m}}^2$. Calculate, how much pressure is increased on a plane surface when both the cube and cuboid made vertically stand.