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3 years ago

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A bird watcher meanders through the woods, walking 1.46 km due east, 0.123 km due south, and 4.24 km in a direction 52.4° north

of west. The time required for this trip is 1.285 h. Determine the magnitudes of the bird watcher's (a)displacement and (b) average velocity.

1 answer:

Karo-lina-s [1.5K]3 years ago

3 0

Answer:

(a). The displacement is 3.11 m.

(b). The average velocity is 2.42 km/hr.

Explanation:

Given that,

A bird watcher meanders through the woods, walking 1.46 km due east, 0.123 km due south, and 4.24 km in a direction 52.4° north of west.

(a). We need to calculate the displacement

Using Pythagorean theorem

$D=\sqrt{(OA)^2+(AB)^2}$

$D=\sqrt{(1.46-4.24\sin52.4)^2+(0.123-4.24\cos52.4)^2}$

$D=3.11\ km$

(b). We need to calculate the average velocity

Using formula of average velocity

$v_{avg}=\dfrac{D}{T}$

Where, D = displacement

T = time

Put the value into the formula

$v_{avg}=\dfrac{3.11}{1.285}$

$v_{avg}=2.42\ km/hr$

Hence, (a). The displacement is 3.11 m.

(b). The average velocity is 2.42 km/hr.

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3. Missing diagram

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