Question
The height of an arrow shot upward can be given by the formula s=v_(0)t-16t^2 where v_(0) is the initial velocity and tis time How long does it take for the arrow to reach a height of 48 ft if it has an initial velocity of 96ft/s ? Round to the nearest hundredth. The equation that represents the problem is 48=96t-16t^2 Solve 16t^2-96t+48=0 Complete the square to write 16t^2-96t+48=0 as DONE V (t+9)^2=-3 (t-3)^2=6 (t-6)^2=12
Solution
4.6
(294 Votos)
Kelly
Mestre · Tutor por 5 anos
Resposta
The arrow takes 3 seconds to reach a height of 48ft.
Explicação
## Step 1The problem involves the physics concept of motion under constant acceleration, specifically the motion of an object thrown upwards. The formula given is
, where
is the height,
is the initial velocity, and
is the time. The problem asks us to find the time it takes for the arrow to reach a height of 48ft, given an initial velocity of 96ft/s.## Step 2We start by setting up the equation that represents the problem, which is
. This equation is derived from the given formula by substituting the given values for
and
.## Step 3Next, we rearrange the equation to the standard quadratic form
, which gives us
.## Step 4We then solve this quadratic equation using the quadratic formula
. Substituting the values of
,
, and
from our equation, we get \(t = \frac{96 \pm \sqrt{(-96)^{2} - 4*16*48}}{2*16}\).## Step 5Solving this gives us two solutions,
and
. However, since time cannot be negative, we only consider the positive root, which is
.