Train a leaves the station traveling at 30 miles per hour. two hours later train в leaves the same station traveling in the same direction at 40 miles per hour. how far from the station was train a overtaken by train b?
(a) 180
(b) 240
(c) 270
(d) 300
(e) 320

(B)  240 miles

Explanation:

As the two trains move uniform motion we apply the following equation:

d= v*t

Where:

d= displacement in miles ( mi)

v= speed in miles per hour (mph).

t= time in hours (h)

Data

vA = 30 mph

vB = 40 mph

tA = ( tB+2 ) h

Kinematic equation of train A

dA= vA*tA

dA= 30*tA Equation (1)

Kinematic equation of train A

dB= vB*tB

dB= 40*tB Equation (2)

Problem development

When train A is overtaken by train B, then, dA = dB

Equation (1) = Equation (2)

30*tA = 40*tB  , tA=tB+2

30*(tB+2 )= 40*tB

30*tB + 60 = 40*tB

60 = 40*tB - 30*tB

60 =10*tB

tB =60/10

tB =6 h

We replace tB =6 h in the equation (2)

dB= 40*6

dB= 240 miles

jupiter is the largest planet in our solar system, having a mass and radius that are respectively, 318 and 11.2 times that of earth. suppose that an object falls from rest near the surface of each planet and that the acceleration due to gravity remains constant during the fall. each object falls the same distance before striking the ground. determine the ratio of the time of fall on jupiter to that on earth.