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Kaylis [27]
2 years ago
5

A 280-m-wide river flows due east at a uniform speed of 4.7m/s. A boat with a speed of 7.1m/s relative to the water leaves the s

outh bank pointed in a direction 26o west of north. What is the (a) magnitude and (b) direction of the boat's velocity relative to the ground
Physics
1 answer:
tamaranim1 [39]2 years ago
7 0

Answer:

(a) The speed is 7.96 m/s

(b) The direction is 76 degree from positive X axis in counter clockwise direction.  

Explanation:

Width of river = 280 m

speed of river, vR = 4.7 m/s towards east

speed of boat with respect to water, v(B,R) = 7.1 m/s at 26 degree west of north

vR = 4.7 i \\\\v(B,R) = 7.1 (- sin 26 i + cos 26 j) = - 3.1 i + 6.4 j

(a) The velocity of boat with respect to ground is

\overrightarrow{v}_{(B,R)}=\overrightarrow{v}_{(B,G)}-\overrightarrow{v}_{(R,G)}\\\\- 3.1 \widehat{i} +6.4 \widehat{j}=\overrightarrow{v}_{(B,G)} - 4.7 \widehat{i}\\\\\overrightarrow{v}_{(B,G)} = 1.6 \widehat{i} + 6.4 \widehat{j}\\\\{v}_{(B,G)} = \sqrt{1.6^2 + 6.4^2}=6.96 m/s

(b) The direction is given  by

tan\theta = \frac{6.4}{1.6} =4\\\\\theta = 76^o

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Check the explanation

Explanation:

This is the step by step explanation to the above question:

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v = 344 m/s

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3 years ago
A graph that shows how position depends on time is a?
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A graph that shows how position is depending on time is known as a Position Time Graph.

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3 years ago
Imagine a system where a block rests on an inclined plane. The block is then given an initial push so that it starts sliding dow
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Answer:

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Explanation:

The statement ''The work done by friction is equal to the sum of the work done by the gravity and the initial push" is correct.

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here, the downward direction signifies the downward motion parallel to the inclined plane.

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Later, after the astronaut throws the wrench, the total momentum is

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5 0
3 years ago
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Hello,

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8 0
3 years ago
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