A watertight car is submerged under water. What force is required to open a door of area 1.12 m2 if the average depth of water at the door is 1.50 m?
It depends on the pressure inside the car. after a few minutes the car will fill with water from holes in the floor etc and only a bubble of air at ambient (water) pressure will remain under the roof (avoid leaky sun roof). At that point the door (or window) will open easily.
To determine the force required to open the door of a watertight car submerged under water, we can use the concept of pressure and area.
Firstly, the pressure exerted by water at a certain depth can be calculated using the formula:
Pressure = density × gravity × depth
Where:
- Density is the density of water (usually taken as 1000 kg/m³)
- Gravity is the acceleration due to gravity (approximately 9.8 m/s²)
- Depth is the height of the water column (1.50 m in this case)
So, the pressure exerted by the water at the door can be calculated as:
Pressure = 1000 kg/m³ × 9.8 m/s² × 1.50 m
Next, we need to find the force required to overcome this pressure. The force can be calculated using the formula:
Force = Pressure × Area
Where:
- Pressure is the calculated pressure exerted by the water
- Area is the area of the door (1.12 m² in this case)
Now, we can substitute the values into the equation:
Force = (1000 kg/m³ × 9.8 m/s² × 1.50 m) × 1.12 m²
By calculating this equation, we can determine the force required to open the door of the watertight car.