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3 years ago

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A motor boat is headed at a velocity of 25 kilometers/hour toward the north, while the velocity of the water current is 12 kilom

eters/hour to the west. What is the magnitude of the boat’s resultant velocity?

1 answer:

Tems11 [23]3 years ago

8 0

Explanation:

CON EL TEOREMA DE PITÁGORAS

<em>v</em> = $\sqrt{(12 km/h)^{2} + (25 km/h)^{2}}$ = 27.7 km/h

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Vsevolod [243]

Answer:

B

Explanation:

490km/h

490km/1h

490000/3600

note: 1h= (60×60)=3600

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ExtremeBDS [4]

Answer:

Explanation:

The rate of conductive heat transfer in watts is:

q = (k/s) A ΔT

where k is the heat conductivity, s is the thickness, A is the area, and ΔT is the temperature difference.

a)

Given k = 52.4 W/m/K, s = 0.014 m, and ΔT = 350-140 = 210 K, we can find q/A:

q/A = (52.4 / 0.014) (210)

q/A = 786,000 W/m²

b)

Given that A = 0.42 m², we can find q:

q = (0.42 m²) (786,000 W/m²)

q = 330,120 W

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q = 330,120 J/s * 3600 s/hr

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c)

If we change k to 1.8 W/m/K:

q = (k/s) A ΔT

q = (1.8 / 0.014) (0.42) (210)

q = 11,340 J/s

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d)

If k is 52.4 W/m/K and s is 0.024 m:

q = (k/s) A ΔT

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The tension in the string with friction would be the biggest because of the involvement of the force of gravity. This would result in that the friction force that is acting on the system. There is no friction in the frictionless system, and only the force of gravity is relevant.

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Read 2 more answers

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3 years ago