Hello everyone! Please, help me understand the following problem:(adsbygoogle = window.adsbygoogle || []).push({});

1. The problem statement, all variables and given/known data

Earth's orbit around the Sun is nearly circular. The period is 1 yr = 365.25 d.

(a) In an elapsed time of 5 d, what is Earth's angular displacement? Solved!

(b) What is the change in Earth's velocity, Δv?Confused!

2. Relevant equations

ω = Δθ/Δt

v = rω

3. The attempt at a solution

I easily solved the first problem doing this: Δθ = (2π x 5 days)/365.25 days = 0.0860 rads

However, whenever I enter a solution for the second problem, the computer does not accept my answer, even though I'm solving it correctly. This is what I did:

First, I tried to solve for the angular velocity of the object. Since the computer wants the answer in meters per second, I converted Δt to seconds:

ω = Δθ/Δt = 0.0860121192 rads / (5 days x 86,400 sec) = 1.99x10^-7 rads/sec

Now, I substitute the distance between the sun and the earth in meters and the angular velocity into v = rω to solve for v.

v = rω = (1.5x10^14 m)(1.99x10^-7 rads/sec) = 2.99x10^7 m/s

The correct answer, according to the computer, should be 2570 m/s.

What am I doing wrong?

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# Homework Help: Circular Motion of earth's orbit Problem

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