A liquid is poured into three vessels of the same base area and equal heights as shown in the figure, then:
                          

The area of cross-section of the wider tube shown in the figure is $800~\text{cm}^2.$ If a mass of $12~\text{kg}$ is placed on the massless piston, then the difference in heights $h$ of the levels of water in the two tubes will be:

The value of g at a place decreases by 2%. Then, the barometric height of mercury:

The height of a mercury barometer is $75 ~\text{cm}$ at sea level and $50 ~\text{cm}$ at the top of a hill. The ratio of the density of mercury to that of air is $10^4.$ The height of the hill is:

A vertical $\mathrm{U}$-tube of uniform inner cross-section contains mercury in both its arms. A glycerin (density$=1.3$ g/cm³) column of length $10$ cm is introduced into one of its arms. Oil of density $0.8$ g/cm³  is poured into the other arm until the upper surfaces of the oil and glycerin are at the same horizontal level. The length of the oil column is:
(density of mercury $=13.6$ g/cm³)
                       
1. $10.4$ cm
2. $8.2$ cm
3. $7.2$ cm
4. $9.6$ cm

A barometer kept in a stationary elevator reads $76 ~\text{cm}.$ If the elevator starts accelerating up, the reading will be:
1. zero
2. equal to $76 ~\text{cm}$
3. more than $76 ~\text{cm}$
4. less than $76 ~\text{cm}$

Which of the following diagrams does not represent a streamline flow?

1.		2.
3.		4.

Three liquids of densities $d,$ $2d$ and $3d$ are mixed in equal proportions of weights. The relative density of the mixture is: