A rectangular piece of wood measuring 20cm by 5cm by 3cm weighs 900kg.Find the greatest pressure the piece of wood can exert if placed on a table.
To find the greatest pressure exerted by the piece of wood, we need to calculate the force exerted by the wood and divide it by the area over which the force is applied.
1. Calculate the volume of the wood:
Volume = Length x Width x Height
Volume = 20cm x 5cm x 3cm = 300 cubic centimeters
2. Convert the volume of the wood to liters:
Since 1 cubic centimeter is equal to 1 milliliter, we have:
Volume = 300 ml
Since 1 liter is equal to 1000 milliliters, we divide the volume by 1000:
Volume = 300 ml ÷ 1000 = 0.3 liters
3. Convert the weight of the wood to newtons:
Since the weight is given in kilograms, we can convert it to newtons by using the gravitational acceleration:
Weight = mass x gravitational acceleration
The gravitational acceleration is approximately 9.8 m/s².
Weight = 900 kg x 9.8 m/s² ≈ 8,820 N
4. Calculate the pressure exerted by the wood:
Pressure = Force / Area
The force exerted by the wood is equal to its weight, and the area over which the force is applied is the contact area between the wood and the table.
Since the wood is rectangular and resting on a table, the contact area with the table is the base area, which is equal to the length multiplied by the width:
Area = Length x Width
Area = 20 cm x 5 cm = 100 cm²
Finally, we can calculate the pressure:
Pressure = 8,820 N / 100 cm²
To convert cm² to m², we divide by 10,000:
Pressure = 8,820 N / 100 cm² ÷ 10,000 = 0.882 Pa
Therefore, the greatest pressure the piece of wood can exert when placed on a table is approximately 0.882 Pascal (Pa).