Force and Pressure

Converting the Unit from cmHg to Pa Pressure in unit cmHg can be converted to Pa by using the formula P = hρgExample 1:Find the pressure at point A, B, C, D, D, E and F in the unit of cmHg and Pa. [Density of mercury = 13600 kg/m³] Answer: Pressure in unit cmHg  Pressure … Read more

Simple Barometer Atmospheric pressure can be measured by a simple barometer. A thick glass tube (at least 1m long) is filled with mercury completely. The open end of the tube is covered with a finger and inverted in a trough of mercury. The height of the mercury is proportional to the atmospheric pressure. Using Simple … Read more

Instruments Used to Measure Atmospheric Pressure Atmospheric pressure can be measured by either a simple barometer, a Fortin barometer an Aneroid barometer. In SPM, most of the questions asked are related to the simple barometer. For Fortin barometer and Aneroid barometer, you only need to know their working principle. Simple Mercury Barometer The Fortin Barometer.This … Read more

Syringe When the piston is pulled up, the atmospheric pressure inside the cylinder will decrease. The atmospheric pressure outside pushes the liquid up into the syringe. Lift Pump Siphon Working Mechanism of Siphon Sucker Hook When the sucker is pressed into place, the air inside is forced out. As a result, the pressure inside the … Read more

Proof of Existence of Atmospheric Pressure The existence of the atmospheric pressure can be proved by the following experiments. Crushing can experiment Water cover with cardboard does not flow out Magdeburg Hemisphere Crushing can experiment When a can filled with hot water is closed and is cooled down rapidly by pouring cold water on it, … Read more

Atmospheric Pressure On the surface of the earth, there is a thick layer of gas called the atmosphere. The atmosphere consists of various types of gas called the atmospheric gas. The atmospheric gases collide on the surface of the earth and hence exert a pressure on the surface of the earth, called the atmospheric pressure. … Read more

Gas Pressure   Gas pressure is the force per unit area exerted by the gas molecules as they collide with the surface of an object. In SPM, especially in paper 2 essay question, you need to know how the gas pressure is produced. (See question below) Question:Explain how gas pressure is produced in a closed … Read more

Dam The wall of the dam is built thicker at the bottom to withstand a higher pressure. The generator is placed at the lower part so that the pressure of the water is high enough to drive the turbine. Submarine In deep sea, the pressure of the water is tremendously high. Hence the body of … Read more

The pressure caused by a liquid has the following characteristics: Pressure in liquid does not depends on the shape of the container. the size of the container. the area of its surface. Pressure increases with depth The deeper the liquid, the faster the liquid spurts out. In conclusion, the pressure in a liquid increases with … Read more

Usually, a U-tube is used to compare and measure the density of liquids. The density of the 2 liquids is related by the equation: h1ρ1 = h2ρ2 Example: Figure above shows a U-tube filled with water and liquid P. Liquid P is insoluble in water. Given that the density of water is 1000kg/m³, find the … Read more