. If the pressure exerted on a floor by a box is 200 KPa. Find the weight of the box, given that the bottom of the box has a contact area of 20cm2.
Answers
Given :
• If the pressure exerted on a floor by a box is 200 KPa
• The bottom of the box has a contact area of 20 cm²
To find :
• Weight of the box
Solution :
Firstly, we shall convert the Pressure and area of contact from KPa and cm² into Pa and m² respectively.
As we know,
→ 1 KPa = 1000 Pa
To convert the value from KPa into Pa multiple the value by 1000.
→ Pressure = 200 × 1000
→ Pressure = 2,00,000
Pressure = 2,00,000 Pa
As we know,
→ 1 cm² = 1/10000 m²
To convert the value from cm² into m² divide the value by 10000.
→ Area = 20/10000
→ Area = 2/1000
Area = 2/1000 m²
Formula to find Pressure :-
→ Pressure = F ÷ A or Pressure = W ÷ A
where,
• F denotes the force
• W denotes the weight
• A denotes the area
So, formula to calculate weight :-
→ Weight = Pressure × Area
Substituting the given values :
→ Weight = 2,00,000 × 2/1000
→ Weight = 200 × 2
→ Weight = 400
Therefore, weight of the box = 400 N