Projectile Motion, with only Displacement and Angle Known.

[n72.75]

Homework Statement

A projectile is fired at an angle of 35° and lands 88.5 Meters Down Range.
Assume no air resistance, and a gravatational acceleration of 9.80665 M/S²

I can get as far as the trig, but it doesn't seem like there is enough information to find time or velocity.

Find Initial Velocity Of the Projectile.

Homework Equations

a = [tex]\frac{(V _f - V _i) }{ t }[/tex]
s = V _i + $$\frac{1}{2}$$ at ²

The Attempt at a Solution

See Attachment.

 

[Melawrghk]

Break up the motion into x&y components.

Since you know the distance, you can write an equation linking Vi and T (total time). Similarly because horizontal speed doesn't change, you can write an equation linking Vi and N=T/2.

Now, what happens when projectile is halfway there (with respect to the y-component of speed)?

 

[nlightner]

I would first clarify that the given information is not enough to solve for the initial velocity of the projectile. In order to do so, we would need to know either the time of flight or the final velocity of the projectile. Without this additional information, we cannot accurately determine the initial velocity.

However, we can use the given information to make some general observations about the motion of the projectile. We know that the projectile has a displacement of 88.5 meters in the horizontal direction and we can assume that it has a displacement of 0 meters in the vertical direction (since it starts and ends at the same height). We also know the angle at which it was fired, which can help us determine its initial velocity in the horizontal and vertical directions.

Using trigonometry, we can determine the initial horizontal velocity (Vx) by using the cosine function: Vx = Vcos(35°). Similarly, we can determine the initial vertical velocity (Vy) by using the sine function: Vy = Vsin(35°). However, without knowing the value of V, we cannot solve for Vx or Vy.

In conclusion, while we can make some general observations about the motion of the projectile, we cannot accurately determine its initial velocity without additional information. It is important to always have enough information and to carefully consider the variables involved when solving for unknowns in a scientific problem.