Chapter 02, Problem 034 In the figure here, a red car and a green car move towar

Question

Chapter 02, Problem 034

In the figure here, a red car and a green car move toward each other in adjacent lanes and parallel to an x axis. At time t = 0, the red car is at xr = 0 and the green car is at xg = 218 m. If the red car has a constant velocity of 24.0 km/h, the cars pass each other at x = 43.9 m. On the other hand, if the red car has a constant velocity of 48.0 km/h, they pass each other at x = 76.0 m. What are (a) the initial velocity and (b) the (constant) acceleration of the green car? Include the signs.

Explanation / Answer

Let the initial velocity be V and accleration of green car be a.

when speed of red car = 24 km/h = 24*5/18 = 6.67 m/s

during the cars meet in t = 43.9/6.67 = 6.58sec

During this distance travelled by green car

d = 218 - 43.9 = 174.1 m

and Disatnce S = vt + 0.5 at^2

174.1 = V * (6.58) + 0.5* a *(6.58)^2

6.58 V + 21.64 a = 174.1 --------------------------------1

now when speed of red car = 48 km/h = 13.34 m/s

time t = 76/13.34 = 5.69 sec

(218 - 76) = V* 5.69 + 0.5* a *(5.69^2)

5.69 V + 16.18 a = 142-------------------------2

solving (1) and (2)

V = 15.35 m/s

a = 3.37 m/s^2

Related Questions

Navigate

• Browse (All)
• Browse C
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.