Question

draw a diagram and tell with a beaker with some water and place a lighted candle is standing position in it occur with the candle with attached to cut it off with their supply for how long it keep burning draw a diagram .I need Diagram​

Answer 1

ANSWER:

1. A diver is 10 m below the surface of water in a dam. If the density of water is 1,000 kgm -3, determine the pressure due to the water on the diver. (Take g = 10 Nkg-1)

Solution

Pressure = h ρ g = 10 × 1000 × 10 = 100,000 Nm-2.

2. The density of mercury is 13,600 kgm-3. Determine the liquid pressure at a point 76 cm below the surface of mercury. (Take g = 10 Nkg-1)

Solution

Pressure = h ρ g = 0.76 × 13,600 × 10 = 103,360 Nm-2

. 3. The height of the mercury column in a barometer is found to be 67.0 cm at a certain place.

What would be the height of a water barometer at the same place? (Densities of mercury and water are 1.36 × 104 kg/m3 and 1.0 × 103 kg/m3 respectively.)

Solution

Let the pressure due to water be h1ρ1g1 = h ρ g, hence;

h1 = h ρ / ρ1= (6.7 × 10-1) × (1.36 × 104) = 911.2 cm or 9.11 m.

U-tube manometer

It is a transparent tube bent into U-shape. When a liquid is poured into a u-tube it settles at equal level since pressure depends on height and they s hare the same bottom.

Consider the following diagrams;

For the levels to differ the pressure P1 must be greater than P2, hence

P1 = P2 + hρg.

If P1 is the lung pressure, P0 is the atmospheric pressure, then if the difference is ‘h’ then lung pressure can calculated as follows.

P1 = P0 + hρg.

Example

A man blows into one end of a U-tube containing water until the levels differ by 40.0 cm. if the atmospheric pressure is 1.01 × 105 N/m2 and the density of water is 1000 kg/m3, calculate his lung pressure.

Explanation: