- #1

lilyxmo

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**Gr. 11 Projectile motion lab?**

## Homework Statement

we are conducting an experiment where a ball is being shot from a cannon from a height of 1.435m

we have already calculated our initial velocity, which is 5.442m/s, by timing and measuring when the ball is shot and lands 5 times. Then find the velocity of those and find the average..

BUT we have to predict where our ball will land and be able to hit a target accurately if given an angle.

**2. Homework Equations and attempts at solving**SO i tried calculating it if we shot the ball at an angle of 35 degrees

and i used this formula:

Δdy = vyΔt + 1/2gΔt^2

then set [up] as positive

so.. gravity is -9.8m/s^2

dy = -1.435m

and vy = 3.121m/s (found the components using vy = v1sinθ)

so i solved for t and got t=0.946s

theeen subbed in (t=0.946) in

dx = vxΔt

where vx = 4.458m/s (solved with v1cosθ)

and got the range of 4.22m

BUT when we actually tried shooting the ball, it landed about 3.25m away which is VERY off from my calculations

We even tried shooting it at 45 degrees to maximize the range and still got a distance of 3.25m! Our distance at 20 degrees was 3.5m, which is greater than the "maximium range"

i really don't understand how to accurately find the range because all my calculations are all off. Is there another factor that needs to be considered? Apparently air resistance does not matter because the ball is only in the air for such a short period of time..