At what speed (in mph) was the potato launched from the gun?

Question

Acceleration due to gravity on Earth is 9.81 m/s² (32 ft/s²) toward the center of the planet. A potato is launched straight up from a potato gun and rises for 3.4 seconds before beginning to fall back down.

Answer 1

use the equation v(t) = v₀+at. You want v₀ which is initial velocity. v @ 3.4 sec is zero because it has stopped going up and its just before going down.

v(3.4) = 0 = v₀ + (-9.91 m/s²)(3.4s)

v₀ = 33.35 m/s