The pressure exerted by the elephant with all four feet on the ground is calculated using the area of its circular feet and the total force. The result is a pressure of 59.7 kPa to three significant figures
To calculate the pressure exerted by the elephant, we need to use the formula P = F/A, where P is the pressure, F is the force, and A is the area. The total force F exerted by the elephant on the ground is given as 30,000 N and this force is distributed over all four feet with circular bases. The area of one circular base A is calculated using the formula for the area of a circle, A = πr², where r is the radius of the circle.
First, we find the area of one foot: A = π (0.2 m)² = π (0.04 m²). This gives A = 0.1256 m² when rounded to four significant figures. As the elephant has four feet, the total area in contact with the ground is 4 (0.1256 m²) = 0.5024 m². Now, we can find the pressure by dividing the total force by the total area: P = 30,000 N / 0.5024 m² = 59724.156 Pa. To give the answer to three significant figures, the pressure the elephant exerts is 59.7 kPa.