Parachute Cord
anyone good with phyisc..please help…?
A parachutist jumps out of an airplane and accelerates with gravity to a maximum velocity of 58.8 m/s in 6 seconds. She then pulls the parachute cord and after a 4 second deceleration, descends at 10 m/s for 60 seconds, reaching the ground. From what height did the parachutist jump?
a.914 m
b.1130 m
c.1520 m
d.1750 m
Use average velocity x time to find distance.
During the first 6 second; [58.8 /2] x 6 = 176.4 m
During the 4 second deceleration: 4 [58.8 + 10] /2 = 137.6 m
During the 60 second of uniform velocity:60×10 = 600.
Total distance =176.4 + 137.6 + 600 = 914 m
—————————————————–
Take 58.8 as 60.
Ist 60*3=180: IInd: 70*2 = 140; and III rd 600
Sum 920. Nearest one is [a]914 m
——————————————————