Need Help With Projectiles off a cliff :/ (1 Viewer)

[kazza9]

hey everyone,
so i keep getting stuck on projectile motion questions that are off cliffs....anyone able to explain how i get the range and time for these type of questions?

 

[Aindan]

to calculate time of flight use
deta y = u(y)t +0.5a(y)t^2
take the cliff as the origin (i.e. delta y = 0), so if the height of the cliff is 100m then when it lands 100m below, delta y = -100 and plug u in. Then you get a quadratic equation, use quadratic formula to calculate t, disregard t as negative, and take the positive solution.

Now that you have time of flight, just use delta x = u(x) t as normal

 

[kazza9]

Thanks but how do I solve the quadratic? I don't do advanced maths...

 

[slyhunter]

For any quadratic,

To get , use the quadratic formula,