posted by Natasha .
An 18-year-old runner can complete a 10.0 km course with an average speed of 4.58 m/s. A 50-year-old runner can cover the same distance with an average speed of 4.36 m/s. How much later (in seconds) should the younger runner start in order to finish the the course at the same time as the older runner?
ytime = 10km * 1000m/km / 4.8m/s = 2083.3 sec
otime = 10km * 1000m/km / 4.36m/s = 2293.6 sec
difference = 210.3 sec
the youngster can loll around for about 3.5 minutes before taking off.
a child traveling 5 m/s on a sleed passes her younger brother. if her average acceleratrion in the sledding hill id 2m/s, how fast is the traveling when she passews her oldeer brother 4s later