Problem 4-12 - Vector components - Part 7 - (A)

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

\(82\; km/hr = 22.8\; m/s\)

Vector coordinates v_i and v_f

\(v_{fx} = 22.8 \cos 12.7^\circ = 22.24\; m/s \\ v_{fy} = -22.8 \sin 12.7^\circ = -5.01\; m/s \\ v_{ix} = 22.8 \sin 38.2^\circ = 14.10\; m/s \\ v_{iy} = 22.8 \cos 38.2^\circ = 17.92\; m/s\)


Correct!

\(a_x = (22.24 - 14.10)/900 = 9.0\times 10^{-3} \;m/s^2\)

Similarly:

\(a_y = (-5.01 - 17.92)/900 = -2.5\times 10^{-2} \;m/s^2\)

 

You have completed this problem.