Physics: Uniform Motion

Submitted by ramelcoletana on

A Metra commuter train leaves
Union Station in Chicago at 12 noon. Two hours later, an
Amtrak train leaves on the same track, traveling at an
average speed that is 50 miles per hour faster than the
Metra train. At 3 PM the Amtrak train is 10 miles behind the
commuter train. How fast is each going?

Tags
Physics

Jhun Vert Sun, 02/28/2021 - 16:39

Consider the figure below:
 

screen_shot_2021-02-28_at_4.21.43_pm.png

 

Given: $v_A = v_M + 50$
 

And from the figure:
$3v_M = v_A + 10$
 

Answers:

$v_M = 30 ~ \text{mph}$

$v_A = 80 ~ \text{mph}$