1)Surprisingly, very few athletes can jump more than 2.2 ft (0.68 m) straight up. Use d = 1/2 gt2 and solve for the time one spends moving upward in a 2.2 foot vertical jump. Then double it for the "hang-time" -- the time one's feet are off the ground.
2)A car takes 10 s to go from v = 0 to v = 30 m/s at approximately constant acceleration. If you wish to find the distance traveled using the equation d = 1/2 at2, what value should you use for a?
3)What is the acceleration of a vehicle that changes its velocity from 130 km/h to a dead stop in 13 s?
2007-10-10 14:43:18 · 1 answers · asked by eaglesblueflag 1 in Science & Mathematics ➔ Physics
2.2=16*t^2
t=sqrt(2.2/16)
t=0.37
or
0.74 hang time
2) solve for a using
v=a*t
30=a*t
a=3
3) convert km/hr to meters per second
1 kilometer per hour = 0.277777778
0=130*0.2778+a*13
a=-2.778 m/s
j
2007-10-11 12:47:26 · answer #1 · answered by odu83 7 · 0⤊ 0⤋