Question
a football is kicked with an initial speed of 80 m/s at an angle of 30 degrees above the horizontal.
A. what is the maximum height that the ball attains?
b. what is the balls hang time? (how long is it in the air)
c. what is the range of the ball? (how far did it go)
A. what is the maximum height that the ball attains?
b. what is the balls hang time? (how long is it in the air)
c. what is the range of the ball? (how far did it go)
Answers
Henry
Vo = 80m/s[30o].
Xo = 80*Cos30 = 69.3 m/s.
Yo = 80*sin30 = 40 m/s.
a. Y = Yo + g*Tr.
0 = 40 - 9.8Tr, Tr = 4.08 s. = Rise time.
h = Yo*Tr + 0.5g*Tr^2.
h = 40*4.08 -4.9*4.08^2 = 81.6 m.
b. Tf = Tr = 4.08 m/s. = Fall time.
Tr+Tf = 4.08 + 4.08 = 8.16 s. = Time in air.
c. Range = Xo*(Tr+Tf) = 69.3 * 8.16 = 565.5 m.
Xo = 80*Cos30 = 69.3 m/s.
Yo = 80*sin30 = 40 m/s.
a. Y = Yo + g*Tr.
0 = 40 - 9.8Tr, Tr = 4.08 s. = Rise time.
h = Yo*Tr + 0.5g*Tr^2.
h = 40*4.08 -4.9*4.08^2 = 81.6 m.
b. Tf = Tr = 4.08 m/s. = Fall time.
Tr+Tf = 4.08 + 4.08 = 8.16 s. = Time in air.
c. Range = Xo*(Tr+Tf) = 69.3 * 8.16 = 565.5 m.