Projectile Motion?

A missile is fired with an initial velocity (vi) of 1,250 feet per second and aimed at a target 8 miles away. Determine the minimum angle of elevation (x) (in degrees) of the missile if the range (r) of the missile in feet is represented by r = (1/32)((vi)^2)(sin(2x)). Roud to only 1 decimal place.

1 Answer
Mar 17, 2018

x approx 29.9^(circ)

Explanation:

We have: r = frac(1)(32) (v_(i))^(2) sin(2x)

Let's plug in the provided values of the range r and the initial velocity v_(i):

Rightarrow 42,240 = frac(1)(32) cdot (1250)^(2) cdot sin(2x)

Note: Value of range was converted from miles to feet.

Rightarrow 1,351,680 = 1,562,500 cdot sin(2x)

Rightarrow sin(2x) = 0.8650752

Rightarrow 2x = 59.89127832...^(circ)

Rightarrow x = 29.94563916...^(circ)

therefore x approx 29.9^(circ)

Therefore, the minimum angle of elevation would be around 29.9^(circ).