Advertisements
Advertisements
प्रश्न
An air bubble of radius 0.2 mm is situated just below the water surface. Calculate the gauge pressure. Surface tension of water = 7.2 × 10−2 N/m.
Advertisements
उत्तर
Given: R = 2 × 10−4 m,
T = 7.2 × 10−2 N/m,
To find: Calculate the gauge pressure = ?
Solution: The gauge pressure inside the bubble = `(2 T)/R`
= `(2 (7.2 xx 10^-2))/(2 xx 10^-4)`
= `(0.144)/(2 xx 10^-4)`
= `(144 xx 10^3)/(2 xx 10^-4)`
= `(144 xx 10^-3 xx 10^4)/(2)`
= `(144 xx 10)/(2)`
= `(1440)/(2)`
= 720 N/m2
= 720 Pa
APPEARS IN
संबंधित प्रश्न
Explain why Atmospheric pressure at a height of about 6 km decreases to nearly half of its value at the sea level, though the height of the atmosphere is more than 100 km
The pressure on a surface increases with an increase in the thrust on the surface.
Water in a lake exerts pressure only at its bottom.
The unit of pressure is .........
Why is the bottom part of the foundation of a building made wider?
Find the thrust required to exert a pressure of 50000 pascals on an area of 0.05 m2 ?
If someone presses a pointed needle against your skin, you are hurt. But if someone presses a rod against your skin with the same force, you easily tolerate. Explain.
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 liquid will
The pressure in a liquid at two points in the same horizontal plane are equal. Consider an elevator accelerating upward and a car accelerating on a horizontal road. The above statement is correct in
Find the pressure 200m below the surface of the ocean if pressure on the free surface of liquid is one atmosphere. (Density of seawater = 1060 kg/m3)
In a hydraulic lift, the input piston had surface area 30 cm2 and the output piston has surface area of 1500 cm2. If a force of 25 N is applied to the input piston, calculate weight/force on output piston.
Consider the statement given below and choose the correct option.
Assertion: Broad straps are used in bags.
Reason: Broad straps last for long.
An empty plastic bottle closed with an airtight stopper is pushed down into a bucket filled with water. As the bottle is pushed down, there is an increasing force on the bottom. This is because
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 brick is kept in three different ways on a table as shown in the following figure. The pressure exerted by the brick on the table will be
 |
 |
 |
| A | B | C |
It is difficult to cut cloth using a pair of scissors with blunt blades. Explain.
If the same force is made to act on a larger area, the pressure ______.
Pressure can be increased by decreasing the force.
Assertion: The pressure at the bottom of the sea is lesser than that near the surface.
Reason: The pressure exerted by a liquid depends upon the depth of the liquid and density of the liquid.
Explain why the cutting instruments are sharpened.
Give reasons why:
cutting edges of knives and axes are sharpened.
What is an Artisan aquifer?
Assertion (A): Air gets thinner with increasing altitude.
Reason (R): The atmospheric pressure increases as we go up in mountains.
Assertion (A): Wide wooden sleepers are kept below railway lines to reduce pressure on the railway tracks and prevent them from sinking into the ground.
Reason (R): Pressure is directly proportional to the area in which it is acting.
Define thrust.
The force exerted by liquid perpendicular to the surface of the body is equal to the product of ______ at that point.
