What happens to the pressure when the area is reduced while keeping the force same?
- AOption (a)
Pressure decreases
- BOption (b)
Pressure increases
- COption (c)
Pressure remains constant
- DOption (d)
Pressure becomes zero
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Correct answer
Pressure increases
Why this answer is correct
The correct answer is Pressure increases.
Key Points
- Pressure is defined as the force exerted per unit area. It is mathematically expressed as:
Pressure = Force/Area (P = F/A).
- If the force remains constant, and the area over which the force is applied is reduced, the pressure will increase. This is because pressure is inversely proportional to area.
- For example, when a sharp knife (smaller area) is used to cut an object, it applies more pressure compared to a blunt knife (larger area) for the same force applied.
- This principle is also utilized in hydraulic systems, where smaller areas are used to generate higher pressures.
- Hence, when the area is reduced while keeping the force constant, the pressure increases.
Additional Information
- Definition of Pressure:
- Pressure is a scalar quantity and is measured in units such as Pascals (Pa) in the SI system.
- 1 Pascal = 1 Newton per square meter (N/m²).
- Applications of Pressure:
- In medical syringes, the small cross-sectional area of the needle increases pressure, allowing the fluid to be easily injected or extracted.
- Hydraulic brakes in vehicles work on the principle of transmitting pressure through a fluid, using smaller areas to generate large forces.
- In construction, pile drivers use smaller areas to exert higher pressure for driving piles into the ground.
- Real-Life Examples:
- Walking on snow with flat shoes is difficult due to lesser pressure distribution, but snowshoes help distribute the pressure over a larger area, preventing sinking.
- High-heeled shoes exert greater pressure on the ground compared to flat-soled shoes because of their smaller contact area.
- Scientific Context:
- The formula P = F/A demonstrates the inverse proportionality between pressure and area when force is constant.
- This relationship is a fundamental concept in fluid mechanics and solid mechanics.
Important Points
- Option 1: Pressure decreases - Incorrect. Since pressure is inversely proportional to area, reducing the area increases pressure, not decreases it.
- Option 3: Pressure remains constant - Incorrect. Pressure cannot remain constant if the area changes while the force is constant, as they are mathematically related.
- Option 4: Pressure becomes zero - Incorrect. Pressure can only become zero if the force is zero or the area approaches infinity, which is not the case here.