# A missile fired

1. Dec 7, 2008

### malay ko

1. The problem statement, all variables and given/known data
A missile is fired with an initial velocity of 85 m/s at an angle of 30 degrees from the horizontal.

A) After how many seconds will the missile reach the highest point?
B) What is the maximum height reached by the missile?
C) Calculate the total horizontal distance traveled by the missile until it hits the ground.

2. Relevant equations

teta = arc tangent Voy/Vox

Vfx = Vocoy teta t

tf = -2 Voy sin teta / g

3. The attempt at a solution

A) tf = -2 Voy sin teta / g
= -2 (85m/s) (sin 30) / 9.81m/s^2
= -85m/s / 9.81m/s^2
= -8.66 s

B and C i dont know which formula to use

2. Dec 7, 2008

### Staff: Mentor

Apply the following formula to the vertical motion:
$$v = v_0 + a t$$
Some useful kinematic formulas are summarized here: Basic Equations of 1-D Kinematics