# Horizontal and Vertical Acceleration?

• October 3rd, 2013, 04:49 PM
cityyy
Horizontal and Vertical Acceleration?
A symmetric projectile spends a total of 20 seconds in the air. It reaches a peak height of 8 meters. How long does it take to reach its peak height? The projectile has a range of 80 meters. What is its horizontal velocity? What is the projectiles horizontal acceleration? What is the projectiles vertical acceleration?

For how long it takes to reach its peak I got (8m)/(20s) = .4m/s
Horizontal Velocity I got (80m/20s) = 4m/s

How do I find the horizontal and vertical acceleration?
• October 3rd, 2013, 04:56 PM
Harold14370
This looks like homework. Just look in your textbook and you will no doubt find the correct formulas. We'll help if you get stuck, but you have to put forth a litlle bit of effort.
• October 3rd, 2013, 04:58 PM
cityyy
There's no textbook for the class.
Is there a formula for vertical and horizontal acceleration?
• October 3rd, 2013, 05:04 PM
Harold14370
If this doesn't do it for you, just do an internet search for "Projectile motion equations" or some such. They are all over the place on the internet.
Projectile Motion Equations Formulas Calculator - Vertical Velocity At Time
• October 3rd, 2013, 05:35 PM
MagiMaster
Two things. Accelerations come from forces, so which forces are acting on the projectile? (Make a list.)

Sceond, you've got the vertical wrong, for two different reasons. Think about the very first question in your post.
• October 3rd, 2013, 05:51 PM
tk421
Quote:

A symmetric projectile spends a total of 20 seconds in the air. It reaches a peak height of 8 meters. How long does it take to reach its peak height? The projectile has a range of 80 meters. What is its horizontal velocity? What is the projectile’s horizontal acceleration? What is the projectile’s vertical acceleration?

For how long it takes to reach its peak I got (8m)/(20s) = .4m/s
Horizontal Velocity I got (80m/20s) = 4m/s

How do I find the horizontal and vertical acceleration?

A very good habit to develop is to check the units of your answers. If the units are wrong, then you know you've made a mistake. This simple habit will save you enormous grief.

In this instance, you are asked to compute a specific time (when the projectile reaches its peak). The answer, whatever it is, should have the dimensions of time. Your answer has the dimensions of velocity, so you should know right away that you've got some re-thinking to do.