Question

A projectile is fired straight up at a speed of 13 m/s. How long does it take to reach the top of its motion? The acceleration due to gravity is 9.8 m/s 2 .

Answer 1

since it is thrown vertically upward, you are only dealing with the vertical components
let [up] be positive and [down] as negative
initial velocity, vi=13m/s
final velocity, Vf=0 m/s --> since you are looking for the time it takes to reach the max height
acceleration, a, = -9.8m/s^2
t=?
you can use the five kinematics equation to solve this problem
\(v_f=v_i +at\) , this equation is more appropriate :)

Answer 2

evaluating this problem in solving for the variable "t"
you'll get
\(\large t=\frac{v_f - v_i}{a}\)

Answer 3

thank you

Answer 4

you're welcome :)
and
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