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lesantik [10]
3 years ago
11

6. A boat with speed of 1.20 km/h relative to the water is heading for a dock 2.29

Physics
1 answer:
Lilit [14]3 years ago
3 0

Answer: 87 min

Explanation:

The speed of the boat S_{boat} will be its speed relative to the river S_{boat-river} plus the the speed of the river S_{river}:

S_{boat}=S_{boat-river}+S_{river} (1)

S_{boat}=1.20 km/h+0.384 km/h (2)

S_{boat}=1.584 \frac{km}{h} (3)

On the other hand, the speed of the boat is given by a relation between its traveled distance d and the time t:

S_{boat}=\frac{d}{t} (4)

Isolating t and knowing d=2.29 km:

t=\frac{d}{S_{boat}} (5)

t=\frac{2.29 km}{1.584 \frac{km}{h}} (6)

t=1.445 h \frac{60min}{1 h}=86.74 min \approx 87 min (7)

Hence the time in minutes is 87 min.

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Answer:

Explanation:

Although there is absolutely NO regard for significant digits, I can help you with this, nonetheless.

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= 2×10^-4

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= (π×0.06×0.4)m²

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