1. Jul 24, 2007

### suxatphysix

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

A racecar is speeding around a racetrack with an average speed of 360 km/hr. The racetrack has a turn that changes the direction of the track from east to 30.0 degrees W of N. The racecar completes this turn in 6.54s.

(a) Draw vectors representing the initial and final velocities of the racecar. Use the graphical method to draw the displacement of the racecar as it goes through the turn in the track.

(b) What is the magnitude and direction of the displacement of the racecar as it goes through the turn?

(c) What is the magnitude and direction of the average acceleration of the racecar as it goes through the turn?

2. Relevant equations

3. The attempt at a solution

converted 360 km/hr to 100m/s

cos30(100m/s)
Vox = 86.60 m/s

sin30(100m/s)
Voy = 50 m/s

$$\Delta$$Rx = 1/2(V1x + Vox)$$\Delta$$t
= 1/2 (86.6m/s)(6.54s)
x= 283.18 m

$$\Delta$$Ry = 1/2(V1y + Voy)$$\Delta$$t
= 1/2(-50m/s)(6.54s)
y = 163.5 m

a = (v1 - v0)/$$\Delta$$t

ax = -150ms / 6.54s = -22.94 m/s$$^{2}$$

ay = 86.6ms / 6.54s = 13.24 ms$$^{2}$$

a = $$\sqrt{(-22.94)^2 + (13.24)^2}$$
a = 26.47 m/s^2

angle = 13.24 / -22.94

angle = -29.985

Hope this is right.
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution