2d Kinematics Question (Need Answers Checked Please)

  • #1

Homework Statement



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?

Homework Equations






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

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

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

a = (v1 - v0)/[tex]\Delta[/tex]t

ax = -150ms / 6.54s = -22.94 m/s[tex]^{2}[/tex]

ay = 86.6ms / 6.54s = 13.24 ms[tex]^{2}[/tex]


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

angle = 13.24 / -22.94

angle = -29.985


Hope this is right.

Homework Statement





Homework Equations





The Attempt at a Solution

 

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