Advertisements
Advertisements
प्रश्न
In problem 10.9, if 15.0 cm of water and spirit each are further poured into the respective arms of the tube, what is the difference in the levels of mercury in the two arms? (Specific gravity of mercury = 13.6)
Advertisements
उत्तर
Height of the water column, h1 = 10 + 15 = 25 cm
Height of the spirit column, h2 = 12.5 + 15 = 27.5 cm
Density of water, ρ1 = 1 g cm–3
Density of spirit, ρ2 = 0.8 g cm–3
Density of mercury = 13.6 g cm–3
Let h be the difference between the levels of mercury in the two arms.
The pressure exerted by height h, of the mercury column:
= hρg
= h × 13.6g … (i)
Difference between the pressures exerted by water and spirit:
`=h_1rho_1g - h_1rho_1g`
= g(25 × 1 – 27.5 × 0.8)
= 3g … (ii)
Equating equations (i) and (ii), we get:
13.6 hg = 3g
h = 0.220588 ≈ 0.221 cm
Hence, the difference between the levels of mercury in the two arms is 0.221 cm.
संबंधित प्रश्न
Explain why Hydrostatic pressure is a scalar quantity even though the pressure is force divided by area.
A plane is in level flight at a constant speed and each of its two wings has an area of 25 m2. If the speed of the air is 180 km/h over the lower wing and 234 km/h over the upper wing surface, determine the plane’s mass. (Take air density to be 1 kg m–3).
For a given thrust, pressure is more on a surface of large j area.
The unit of thrust is ..........
The feet of lizards act like
A normal force of 200 N acts on an area of 0.02 m2. Find the pressure in pascal.
Calculate the pressure in pascal exerted by a force of 300 N acting normally on an area of 30 cm2.
Water flows through a horizontal tube of variable cross section. The area of cross section at A and B are 4 mm2 and 2 mm2 respectively. If 1 cc of water enters per second through A, find (a) the speed of water at A, (b) the speed of water at B and (c) the pressure difference PA − PB.
Match the following.
| 1. | Density | hρg |
| 2. | 1 gwt | Milk |
| 3. | Pascal’s law | `"Mass"/" Volume"` |
| 4. | Pressure exerted by a fluid | Pressure |
| 5. | Lactometer | 980 dyne |
A water tank has four taps fixed at points A, B, C, D as shown in the following figure. The water will flow out at the same pressure from taps at
A chapatti maker is a machine which converts balls of dough into chapatties. What effect of force comes into play in this process?
If the same force is made to act on a larger area, the pressure ______.
Pressure is directly proportional to the area of contact.
Why dams are made stronger and thicker at the bottom than at the top?
All flowing substances, both liquids, and gases are called ______.
Hot air is ______ dense than ordinary air.
The force exerted by liquid perpendicular to the surface of the body is equal to the product of ______ at that point.
A vessel filled with water is kept on a weighing pan and the scale adjusted to zero. A block of mass M and density ρ is suspended by a massless spring of spring constant k. This block is submerged inside into the water in the vessel. What is the reading of the scale?
