A piece of solid weighs 120 g in air, 80 g in water and 60 g in a liquid. The relative density of the solid and that of the liquid are respectively :

1. 3, 2

2. 2,$\frac{3}{4}$

3. $\frac{3}{2}$, 2

4. 3, $\frac{3}{2}$

An inverted bell lying at the bottom of a lake 47.6 m deep has 50 cm³ of air trapped in it. The bell is brought to the surface of the lake. The volume of the trapped air will be: (atmospheric pressure = 70 cm of Hg and density of Hg = 13.6 g/cm³) 

1. 350 cm³                               

2. 300 cm³

3. 250 cm³                               

4. 22 cm³

A siphon in use is demonstrated in the following figure. The density of the liquid flowing in the siphon is 1.5 gm/cc. The pressure difference between the point P and S will be:
            

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

A body of density d₁ is counterpoised by Mg of weights of density d₂ in air of density d. Then the true mass of the body is

1. M                                   

2. $\mathrm{M}\left(1-\frac{\mathrm{d}}{{\mathrm{d}}_2}\right)$

3. $\mathrm{M}\left(1-\frac{\mathrm{d}}{{\mathrm{d}}_1}\right)$                       

4. $\frac{\mathrm{M}(1-\mathrm{d}/{\mathrm{d}}_2)}{(1-\mathrm{d}/{\mathrm{d}}_1)}$

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

A barometer kept in a stationary elevator reads 76 cm. If the elevator starts accelerating up, the reading will be:

A closed rectangular tank is completely filled with water and is accelerated horizontally with an acceleration a towards right. Pressure is (i) maximum at, and (ii) minimum at

1. (i) B (ii) D

2. (i) C (ii) D

3. (i) B (ii) C

4. (i) B (ii) A

A beaker containing a liquid is kept inside a big closed jar. If the air inside the jar is continuously pumped out, the pressure in the liquid near the bottom of the beaker will

1. Increase

2. Decrease

3. Remain constant

4. First decrease and then increase

A given shaped glass tube having uniform cross section is filled with water and is mounted on a rotatable shaft as shown in figure. If the tube is rotated with a constant angular velocity $\mathrm{\omega }$ then

1. Water levels in both sections A and B go up

2. Water level in Section A goes up and that in B comes down

3. Water level in Section A comes down and that in B it goes up

4. Water levels remains same in both sections