Question

an athlete executing a long jump leaves the ground at a 28 degree angle and lands 7.6 m away.

part a )what was the takeoff speed ?

part b) if this speed were increased by just 8.0% , how much longer would the jump be ?

for part a) i got roughly 9.48 but i am getting the incorrect answer for part b)
please and thank you

Answer 1

a. D = Vo^2*sin(2A)/g = 7.6 m.
Vo^2*sin56 / 9.8 = 7.6.
0.08460*Vo^2 = 7.6.
Vo^2 = 7.6 / 0.08460 = 89.84.
Vo = 9.48 m/s.

b. Vo = 1.08 * 9.48 = 10.24 m/s.
D = (10.24)^2*sin56/9.8 = 8.86.

D2 - D1 = 8.86 - 7.6 = 1.26 m. Longer.