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3 years ago

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2. A truck is traveling east through mud that is slowing down its speed. With west defined as negative, which of the following i

s correct? A. Both its velocity and acceleration are negative. B. Both its velocity and acceleration are positive. C. Its velocity is positive but its acceleration is negative. D. Its velocity is negative but its acceleration is positive. E. Both its velocity and acceleration are 0, since both properties are vectors.

1 answer:

Lynna [10]3 years ago

3 0

Hi! The answer is C

As west is defined as negative, the trucks velocity is positive, since its travelling east. But its speed (absolute value of velocity) is decreasing, that means that the acceleration is negative.

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A wire 6.90 m long with diameter of 2.15 mm has a resistance of 0.0320 Ω. Find the resistivity of the material of the wire. rho

spayn [35]

<h2>Answer:</h2>

1.68 x 10⁻⁸Ωm

<h2>Explanation:</h2>

The resistance (R) of a wire is related to its length(L), its material resistivity(ρ) and its crossectional area(A) as follows;

R = ρL/A ------------------------(i)

Where;

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From the question;

L = 6.90m

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First calculate the crossectional area (A) of the wire as follows;

A = πd² / 4

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R = ρL/A

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Answer:

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Explanation:

From the question we are told that

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3 years ago