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## Homework Statement

Two tugboats are pulling on a large log, as shown in the following diagram. The log has a mass of 250 kg and is initially at rest. How far have the tugboats moved the log after 10 s?

## Homework Equations

c

^{2}= a

^{2}+ b

^{2}- 2abcosC

c = (a

^{2}+ b

^{2}- 2abcosC)

^{1/2}

## The Attempt at a Solution

[/B]

c

^{2}= a

^{2}+ b

^{2}- 2abcosC

c = (a

^{2}+ b

^{2}- 2abcosC)

^{1/2}

c = [(400 N)

^{2}+ (800 N)

^{2}- 2 (400 N) x (800 N) cos 150°]

^{1/2}

c= 1164 N

sinβ/800 N = sin 150°/ 1164 N

β = 20°

(To determine the angle for F

_{net}, subtract 10° from 20°, which equals 10°, as this results in the angle needed to describe the direction for F

_{net}.)

Fnet = 1164 N [W 10° N]

a = 1164 N [W 10° N] / 250 kg

= 4.66 m/s

^{2}[W 10° N]

Δd = ½ 4.66 m/s

^{2}[W 10° N] x (10 s)

^{2}

Δd = 233 m [W 10° N]

The tugboats have moved the log 233 m [W 10° N] after 10 seconds.

Is this correct?