PHYSICS [2 Mark Question Answer]

If the army tanks did not have caterpillar tracks, they would sink in the marshy areas. Their surface area of contact would be too less and they will exert more force and pressure on the ground.

A blunt tip nail has bigger area of contact which reduces the pressure and the effect of force is reduced. So, it won’t be easy to pierce it through a given material and hence discarded.

If air pressure in the tubes would be more, then the tyres will inflate and their area of contact with the ground will decrease and it will exert more pressure and might burst. If air pressure is less, the tyres would deflate, area of contact with ground will increase and less pressure (less force) would lead to slow speed, more friction and wear and tear of the tires.

Applications of pressure :

• Increasing pressure – Example : Knives, blades, scissors, etc have sharp edges as sharp edges have a small surface area. This increases the pressure and we can cut a given substance easily.
  
  
• Decreasing pressure – Example : Heavy vehicles that carry huge loads in them are provided with extra tyres to increase the surface area and thus keep the pressure on the ground reduced.

Safety pins and drawing pins have narrow and sharp tips because the smaller surface area of the tip causes a high pressure and makes it easier for these pins to pierce through a given material.

Pressure is greater at 10 m below the surface of the sea as the deeper we go in the sea, more is the weight of water on top and hence more is the force it applies and hence more pressure.

Pressure is defined as the amount of force acting per unit area. It is denoted by P. Mathematically, it is expressed as Living Science Physics Class 6 ICSE Solutions Chapter 5 Pressure - 2 Its unit is N/m2 or pascal (Pa). Factors on which pressure exerted by a body depends are : (i) Magnitude of force (thrust) – Greater the force, more is the pressure. (ii) Area of contact – Greater the area of contact, lesser is the pressure.