Problem 4-12 - Vector components - Part 7 - (C)
A car is travelling along a winding highway at a constant speed of \(82\; km/h.\) At 3:00 p.m., the car is heading \(38.2^\circ\) east of north, and at 3:15 p.m. it is heading \(12.7^\circ\) south of east. Define the \(+x\) and \(+y\) directions to be east and north, respectively. Use Eq. 4-8 to determine the \(x\)- and \(y\)-components of the average acceleration during this time interval.
Accumulated Solution
\(82\; km/hr = 22.8\; m/s\)
\(v_{fx} = 22.8 \cos 12.7^\circ = 22.24\; m/s \\ v_{fy} = -22.8 \sin 12.7^\circ = -5.01\; m/s \\ v_{ix} = 22.8 \sin 38.2^\circ = 14.10\; m/s \\ v_{iy} = 22.8 \cos 38.2^\circ = 17.92\; m/s\)
No. You have used the \(y\) component of \(v_i\) instead of the \(x\) component.