Question

Nathan is walking to the store and sees a snake slithering across the sidewalk. He jumps over it with an initial vertical velocity of 10 ft/s. How long does it take for Nathan to land back on the ground

Answer 1

`0.62\:\mathrm{s}`

Step-by-step explanation:

Since the universal SI unit for velocity is meters/second, let's convert ft/s to m/s:

`10\:\mathrm{ft/s}=3.048\:\mathrm{m/s}`

We can use the following kinematics equation to solve this question:

`v_f=v_i+at`

What we know:

• The initial velocity,
  `v_i`, is
  `3.048\:\mathrm{m/s}`

• (physics concept) The final velocity must be equal in magnitude but opposite in direction to the initial velocity (
  `v_f=-3.048\:\mathrm{m/s}`)
• Acceleration,
  `a`, is acceleration due to gravity at about
  `9.8\:\mathrm{m/s}`

Solving for
`t`:

`-3.048=3.048+(-9.8t),\\-6.096=-9.8t,\\t=(-6.096)/(-9.8)\approx \boxed{0.62\:\mathrm{s}}`