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a garden hose with an internal diameter of 1.2 cm is connected to a (stationary) lawn sprinkler that consists merely of a container with 27 holes, each 0.29 cm in diameter. if the water in the hose has a speed of 0.83 m/s, at what speed does it leave the sprinkler holes?

User Vedanshu
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The water leaves the sprinkler holes at a speed of approximately 0.53 meters per second.

At what speed does it leave the sprinkler holes?

Radius of the hose: r hose = 1.2 cm / 2 = 0.6 cm

Area of the hose: A hose = π * r hose² ≈ 1.13 cm²

Radius of a hole: r hole = 0.29 cm / 2 = 0.145 cm

Area of one hole: A hole = π * r hole² ≈ 0.066 cm²

Total area of all holes: A holes = 27 * A hole ≈ 1.78 cm²

This principle states that the mass flow rate of an incompressible fluid remains constant throughout a closed system.

In this case, the system is the hose and the sprinkler container.

Mass flow rate = density * velocity * area

Assuming the water density remains constant (around 1000 kg/m³), we can equate the mass flow rate in the hose to the total mass flow rate through all the sprinkler holes:

ρ * v hose * A hose = ρ * v holes * A holes

v holes = (v hose * A hose) / A holes

v holes = (0.83 m/s * 1.13 cm²) / 1.78 cm²

v holes ≈ 0.53 m/s

Therefore, the water leaves the sprinkler holes at a speed of approximately 0.53 meters per second.

User MrWolf
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