Angle of fuzzy dice when moving...Just want to check...

coneheadceo

1. The problem statement, all variables and given/known data
a pair of fuzzy dice hang from your mirror. While you accelerate from a stop on a horizontal surface to 28 m/s in 6 s, what angle θ does the string make with the vertical?

2. Relevant equations

tan θ = Y/X

a = ΔV / Δt

3. The attempt at a solution

Just want a double check:

So we can use the accelerations to figure out the angle....

Ay = 9.8 m/s^2

Ax = (Δ V)/ Δ (t) = (28 m/s - 0)/(6 - 0) = 4.7 m/s^2

tan θ = 4.7 / 9.8 = 25.6°

gneill

Your method is correct. Two things to keep in mind:
1. Don't be too free with the "=" symbol; the angle is not the same as the tan of the angle.
2. Keep a few extra decimal places in intermediate results and only round at the end for the final value.