# Homework Help: Explaining the relationship between launch angle and displacement

1. May 6, 2010

### josh1234

Moderator's note: two threads merged into one. -- Redbelly98

1. The problem statement, all variables and given/known data
what is the relationship between the launch angle and the displacement of a projectile,
is it possible to say that the launch angle is proportional to displacement, can it be done mthematically by using physics equations?
for example we can say that with the equation F=ma
the force is proportional to the acceleration as, when the force increases so does the acceleration and vice versa. and mass is inversley proportional

2. Relevant equations

d = v^2(sin2A)/g

where d, is displacement of the projectile in the horizontal, v is the initial or final velocity? A, is the launch angle of the projectile and g, the accleration de to gravity.

3. The attempt at a solution
i understand the equation and and am able to derive it from the relevent motion equations

Last edited by a moderator: May 9, 2010
2. May 6, 2010

In projectile motion, both diplacement and velocity depend on the launch angle. Of course there exists a set of equation to describe this type of motion. It's very easy to find it on the internet.

3. May 7, 2010

### josh1234

how to explain relationship between launch angle and displacement x direction

1. The problem statement, all variables and given/known data
what is the relationship between the launch angle and the displacement of a projectile,
is it possible to say that the launch angle is proportional to displacement, can it be done mthematically by using physics equations?
for example we can say that with the equation F=ma
the force is proportional to the acceleration as, when the force increases so does the acceleration and vice versa. and mass is inversley proportional

2. Relevant equations

d = v^2(sin2A)/g
http://en.wikipedia.org/wiki/Range_of_a_projectile" [Broken]

where d, is displacement of the projectile in the horizontal, v is the initial or final velocity? A, is the launch angle of the projectile and g, the accleration de to gravity.

3. The attempt at a solution
i understand the equation and and am able to derive it from the relevent motion equations

Last edited by a moderator: May 4, 2017
4. May 7, 2010

### Staff: Mentor

Re: how to explain relationship between launch angle and displacement x direction

You have the equation that describes the relationship.
Does that equation describe a proportion?

I don't understand what it is that you are trying to do.

5. May 7, 2010

### kuruman

Re: how to explain relationship between launch angle and displacement x direction

"Proportional" means more than just that if the projection angle increases so does the horizontal displacement. It means that if one quantity increases by a certain factor, the other should also increase by the same factor. In other words, if, say, you double the angle, the displacement also doubles. Is this the case for projectile motion? What is the horizontal displacement when the angle is 45o and what is it when the angle doubles to 90o?

6. May 7, 2010

### josh1234

Re: how to explain relationship between launch angle and displacement x direction

its not possible is it?,

to say that when the angle increases so does the displacement, because when the angle increases by a factor more than 45 degrees the displacement infact decreases and when the angle decreases by a factor less than 45 degrees the dislacement will also decreases.

am i correct in saying this? or incorrect?

7. May 7, 2010

### SaintsTheMeta

Re: how to explain relationship between launch angle and displacement x direction

correct josh, the relationship varies at every different angle