CHAPTER 3: FORCES & PRESSURE

Defined as force acting normally per unit area of the surface.

Unit : 1 Pa = 1 Nm-2

Factor affect the pressure ;Force area of the surfacemass

Factors affect the pressure

Example question;

1.The diagram given shows

the block of cuboid 0.5m x 0.7m

x 0.9m. Its weight is 15 N.

Calculate :

a) A maximum pressure

b) A minimum pressure

Applications :

1. knife, sole with studs, thumbtacks, etc.

2. Tyre of tractor, snowshoes, feet of elephant,

Exercise ;

exercise1. A pressure of 1000 Pa is acting on a floor of area 012. m2.

what is the resultant force produce?

2. A women wears a pair of shoes where the total surface area in contact is 60 cm2. if the pressure on the floor due to this woman is 75000 Nm-2, what is the weight of the woman?

3. A wooden cuboid has a dimension 0.4m ×0.01 m × 0.2 m and has a mass of 640 g. determine the smallest pressure produced by the cuboid when it is placed on a flat surface?