Question

$\large\sf{Hi!}$

calculate the greatest and the least pressure exerted by a metal block of size 20× 8 cm× 5cm and having a mass of 5 kg?

ɴᴏᴛᴇ :- ɴᴏ ꜱᴘᴀᴍᴍᴇᴅ ᴏʀ ɪʀʀᴇʟᴇᴠᴀɴᴛ ᴀɴꜱᴡᴇʀꜱ!!! ᴡᴀɴᴛ ꜱᴛᴇᴘꜱ ᴛᴏᴏ!!​

Answer 1

Explanation:

pressure = force / Area

accn due to gravity = 10m/s2

so when area is less pressure is more

area is least in case of 8*5= 40 cm^2

so pressure = (5*10)/{(40)/100*100}= 12500pascal

in case of maximum area pressure must me less

area= 20*8= 160 cm^2

so pressure is = 5*10(gravity)/160/100*100

=3125 pascal

Answer 2

Given :-

• Dimension of Block = 20 cm × 8 cm × 5 cm

• Mass of Block = m = 5 Kg

As we know by a relation of Pressure that,

P = F/A

Here, P is the Pressure, F is the Force and A is the area.

Force = Mass × Acceleration due to gravity.

Here, we have acceleration due to gravity because the only acceleration is acting on the body.

F = 5 × 10

F = 50 N

Again,

For having least Pressure, we need greatest area from the given Dimension because Pressure is inversely proportional to Area.

Area = A = (20 × 8) cm²

A = 160 cm²

A = 160 × 10-⁴ m²

Now,

P = 50/160 × 10-⁴

P = 50 × 10⁴/160

P = 3150 Pa

Again,

For greatest Pressure, we need least Area.

A' = (8 × 5) cm²

A' = 40 cm²

A' = 40 × 10-⁴ m²

Now,

P' = F/A'

P' = 50/40 × 10-⁴

P' = 50 × 10⁴/40

P' = 12500 Pa

$\bf{Answer}$