A jet plane lands with a speed of 107.1 m/s
and accelerates at a rate of −5 m/s^2
as it
comes to rest.
From the instant the plane touches the runway, what is the time needed before it can
come to rest?
Answer in units of s

Question

A jet plane lands with a speed of 107.1 m/s
and accelerates at a rate of −5 m/s^2
as it
comes to rest.
From the instant the plane touches the runway, what is the time needed before it can
come to rest?
Answer in units of s

anonymous · Answer

$$\large {v_i=107.1\ m/s \ v_f = 0\ m/s\ a = -5\ m/s^2 }$$

Look through your formulas for something that has $$\huge v_i, v_f, v_a, \  {\large \textrm{and}} \ \Delta t$$

anonymous · Answer

Va=(Vf+Vi)/2

anonymous · Answer

Sorry, I meant $\large a$, not $\large v_a$.

anonymous · Answer

So, look for a formula that has all of the following:

$\huge v_i, v_f, a, \  {\large \textrm{and}} \ \Delta t$

anonymous · Answer

a= Vf - Vi / Δt

anonymous · Answer

Yup. Now just plug in your values and solve for $\Delta t$.

anonymous · Answer

okay:) thank you:)