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3 years ago

If a river current is 8.0 m/s, and a boat is traveling 10.0 m/s upstream, what is the boat’s speed relative to the riverbank?

Physics

2 answers:

Feliz [49]3 years ago

5 0

Answer:

The relative speed of the boat is found to be - 2 m/s or 2 m/s in opposite direction to the river current.

Explanation:

Let us, consider the direction of river as the reference of positive direction. Hence,

Speed of River = Vr = 8 m/s

Since, the boat is traveling upstream. The upstream direction means that the boat is traveling in the opposite direction of the river current. Therefore, its direction will be negative. Hence,

Speed of boat = Vb = - 10 m/s

Now, the relative speed will be the vector sum of both speeds, with relative directions:

Relative Speed = V = Vr + Vb

V = 8 m/s - 10 m/s

V = - 2 m/s

This shows that the magnitude of speed of boat is 2 m/s and its direction will be opposite to that of river current.

Norma-Jean [14]3 years ago

3 0

If the boat is i travling at 10 m/s and the river is 8.0 m/s the boats speed is 18.0 m/s

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ArbitrLikvidat [17]

Answer:

0.0065 m³

Explanation:

Apparent weight = weight − buoyancy

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V = 0.0065 m³

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3 years ago

How much work do you do on a 15 N book in lifting it straight up for a distance of 0.40 meters?

astra-53 [7]

Answer:

Work done, W = 6 J

Explanation:

It is given that,

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The weight of the book is acting in downward direction and the book is lifted straight up, it means angle between them is 180 degrees. Work done is given by :

$W=Fd\cos180\\\\W=15\times 0.4\times \cos180\\\\W=-6\ J$

So, the magnitude of work done in lifting the book is 6 joules.

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3 years ago

A diver shines an underwater searchlight at the surface of a pond (n = 1.33). At what angle (relative to the surface) will the l

allsm [11]

Answer:

41.2°

Explanation:

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The critical angle is the angle of incidence in the denser medium when the angle of incidence in the less dense medium is 90°.

Since

n= 1/sin C

C= sin^-(1/n)

C= sin^-(1/1.33)

C= 48.8°

Hence angle of incidence= 90-48.8 = 41.2°

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3 years ago

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Vlad1618 [11]

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3 years ago

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Tpy6a [65]

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Angular acceleration = (-7700 rpm) / (2.5 sec)

Angular acceleration = -3,080 rev per minute / sec

That's a perfectly good and true answer to the question, but the units are ugly. We really need to fix the units, and convert them into something prettier before we hand in this assignment.

1 rev = 2π radians, and

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3 years ago