Pressure And Properties of Matter - SS1 Physics Past Questions and Answers - page 2
Pascal's principle is the basis for the operation of:
A hydraulic jack
A barometer
A thermometer
A voltmeter
Explain Pascal's principle and its significance in fluid mechanics.
Pascal's principle states that when pressure is applied to a fluid in a confined space, the pressure is transmitted equally in all directions. This means that any change in pressure at one point in a fluid will result in an equal change in pressure at all other points in the fluid. This principle is fundamental in hydraulic systems, where the application of a small force to a small area can generate a larger force on a larger area. Pascal's principle allows for the amplification of force in hydraulic systems, making it useful in various applications such as hydraulic lifts and brakes.
What is atmospheric pressure?
The pressure exerted by the Earth's atmosphere
The pressure exerted by gases in space
The pressure exerted by water bodies
The pressure exerted by underground rocks
Which instrument is commonly used to measure atmospheric pressure?
Thermometer
Barometer
Hydrometer
Anemometer
What happens to atmospheric pressure as altitude increases?
It increases
It decreases
It remains constant
It fluctuates randomly
Explain the concept of atmospheric pressure and how it is measured using a barometer.
Atmospheric pressure is the force per unit area exerted by the Earth's atmosphere on objects within it. It is caused by the weight of the air above a particular point. A barometer is an instrument used to measure atmospheric pressure.
The most common type of barometer is the mercury barometer, which consists of a long glass tube filled with mercury and inverted into a dish of mercury. The height of the mercury column in the tube represents the atmospheric pressure. When the atmospheric pressure increases, the mercury column rises, and when it decreases, the mercury column falls. By measuring the height of the mercury column, we can determine the atmospheric pressure.
Discuss the factors that affect atmospheric pressure and how they contribute to variations in pressure.
Atmospheric pressure is influenced by several factors, including altitude, temperature, humidity, and weather conditions. As altitude increases, atmospheric pressure decreases because there is less air above that point exerting a downward force.
Temperature affects atmospheric pressure through its impact on air density. Warmer air is less dense and exerts lower pressure, while cooler air is denser and exerts higher pressure. Humidity, or the amount of water vapour in the air, also affects atmospheric pressure. Moist air is less dense than dry air, leading to slightly lower pressure. Weather conditions such as high or low-pressure systems can cause temporary variations in atmospheric pressure.
Which of the following statements best describes buoyancy?
The force exerted by an object on a fluid
The force exerted by a fluid on an object submerged in it
The force exerted by gravity on an object
The force exerted by an object on a solid surface.
According to Archimedes' principle, the buoyant force acting on an object submerged in a fluid is equal to:
The weight of the object
The volume of the object
The density of the object
The weight of the fluid displaced by the object.
When an object is fully submerged in a fluid, the buoyant force acting on it is:
Equal to its weight
Greater than its weight
Less than its weight
Independent of its weight.