Two trains leave the rail road station at 1215pm The first t

Two trains leave the rail road station at 12:15pm. The first train travels along a straight track at 82 mph. The second train travels at 71 mph along another straight track that makes an angle of 105degree with the first track. At what time are the trains 425 miles apart? Round your answer to the nearest minute.

Solution

we have to calculate relative speed post

let v1 be velocity of first train along rack =82 mph

let v2 be velocity of second train making 105 degree with track =71mph

v2 along track will be 71cos(105 degree)

=71(-0.2588)

=-18.37 mph

relative speed =82-(-18.37) mph

=100.37mph

for travelling 425 miles time taken

=4.23 hour

time will be 4.29 pm

thank you