# Key equation with uniform acceleration and projectile motion

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Hi guys, I'm Liszzy newly join physic group. How are you everyone? I'm doing my canadian diploma in physic and need help from you guys. I've doubt in Kinematic chapter especially the key equation with uniform acceleration and projectile motion. Kindly please send me if there is any link or notes about kinematic topic for better understanding :) Thank you and have a wonderful day

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• berkeman

CWatters
Homework Helper
Gold Member
Hi Liszzy, Which equation and what is your doubt? The key to understanding simple projectile motion is to treat the motion in the horizontal and vertical separately. The horizontal part is at constant velocity. The vertical part is at constant acceleration. Write two equations, one for each and then solve the simultaneous equations to find whichever parameter you need.

• Liszzy
Thanks for the explanation mate :) If you increase/decrease the variable what effect you think it will have on the motion of the projectile. Will the projectile go farther? Higher? Stay in the air longer? Is there an optimum value to make the projectile go as far as possible?

• sysprog
CWatters
Homework Helper
Gold Member
Which variable?

fresh_42
Mentor
2021 Award
Thanks for the explanation mate :) If you increase/decrease the variable what effect you think it will have on the motion of the projectile. Will the projectile go farther? Higher? Stay in the air longer? Is there an optimum value to make the projectile go as far as possible?
There is, the angle of the shot. You can guess it's correct value, but better would be to prove it the way suggested.

• Liszzy
Thanks for the explanation mate :) If you increase/decrease the variable what effect you think it will have on the motion of the projectile. Will the projectile go farther? Higher? Stay in the air longer? Is there an optimum value to make the projectile go as far as possible?
For a static planar non-sloped surface model with constant perpendicular gravity, and assuming less than escape velocity, launched projectiles, e.g. bolts shot from a crossbow, at 45° will travel the maximum distance, and at 90° (i.e. straight up) will go highest and stay in the air longest.

• Liszzy