(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

This is an output of a c program example given by my professor. I have written a program that makes it as far as calculating everything but impact. I have all equations figured out except for how the time of impact was calculated.

Enter initial magnitude (0 to 250 m/s): 100

Enter initial angle (0 to 90 degrees): 45

Enter starting time (s): 7

Enter time step (s): 0.1

t x(t) y(t) H(x)

------------------------------------

7.00 494.975 255.630 216.917

7.10 502.046 255.785 226.366

7.20 509.117 255.842 235.990

7.30 516.188 255.801 245.777

Impact occurred between t= 7.30 s and 7.40 s.

2. Relevant equations

not sure of the relevant equations, but i tried to calculate using these formulas:

Vx = 100 × Cos 45° =

Viy = 100 × Sin 30° =

Vfy = - Viy

t = ( Vfy - Viy ) / a Time of vertical flight

t = ( -70.17 - 70.17 ) / -9.8

t = ?

being we already know the time step, where am i going wrong here?

3. The attempt at a solution

I am getting an answer of -14.28. I trying to figure out this impact equation to incorporate it into the above program. I am writing this program and I am almost done but I cant figure out how the professor figured out when the impact occurred?

Thanks!

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# Homework Help: Projectile motion time of impact

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