The weight of an object is the force it exerts due to gravity. Pressure is force per unit area, or force divided by area over which the pressure is exerted.
1. For Jo:
force = 500 N
area = 0.0001 m^2
pressure = F/A = 500N/0.0001m^2 = 5,000,000 N/m^2 or 5000 kPa exerted by Jo's feet.
2. For Dumbo:
force = 50,000 N
area = 0.8m^2
pressure = 50,000N/0.8m^2 = 62,500 N/m^2 or 62.5 kPa...
The weight of an object is the force it exerts due to gravity. Pressure is force per unit area, or force divided by area over which the pressure is exerted.
1. For Jo:
force = 500 N
area = 0.0001 m^2
pressure = F/A = 500N/0.0001m^2 = 5,000,000 N/m^2 or 5000 kPa exerted by Jo's feet.
2. For Dumbo:
force = 50,000 N
area = 0.8m^2
pressure = 50,000N/0.8m^2 = 62,500 N/m^2 or 62.5 kPa exerted by Dumbo's feet.
3a. Dumbo the elephant exerts the larger force. His weight is 100 times that of Jo.
3b. Jo exerts more pressure, 5,000,000 N/m^2 compared to 62,500 N/m^2 for Dumbo the elephant. The reason Jo can weigh much less yet exert more pressure is because her weight is acting on a much smaller area than Dumbo's.
4. Jo will sink further into the ground because she exerts more pressure on the ground.
A note on pressure unit conversions: One Newton per meter squared is called a Pascal. One kiloPascal, or kPa, is equal to 1000 Pascals.
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