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2 years ago

11

you spray your sister with water from a garden hose. the water is supplied to the hose at a rate of 0.649x10-3 m^3/s and the dia

meter of the nozzle you hold is 5.45x10^-3 m. at what speed does the water exit the nozzle?

1 answer:

Ivanshal [37]2 years ago

7 0

Answer:

27.82 m/s

Explanation:

The radius of the hose is half of its diameter

$r = d/2 = 5.45\times10^{-3}/2 = 0.002725 m$

So its area must be

$A = \pi r^2 = \pi 0.002725^2 = 2.33\times10^{-5} m^2$

The speed of water coming out of the hose is its flow rate divided by the cross-section area of the hose

$v = \dot{V}/A =0.000649 / 2.33\times10^{-5} = 27.82 m/s$

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Where:

$P=300J/min=5J/s=5W$ is the energy radiated by a blackbody radiator per second, per unit area (in Watts). Knowing $1W=\frac{1Joule}{second}=1\frac{J}{s}$

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$T=727\°C=1000.15K$ is the effective temperature of the body (its surface absolute temperature) in Kelvin.

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