An archer shoots an arrow at 83.0 m/s at a 62.0 degree angle. If the ground is flat, how much time is the arrow in the air?

Respuesta :

The time of flight is 15.0 s

Explanation:

The motion of the arrow is the motion of a projectile, which consists of two separate motions:

  • A uniform motion along the horizontal direction, with constant velocity
  • A uniformly accelerated motion along the vertical direction, with constant acceleration [tex]g=9.8 m/s^2[/tex] towards the ground

From the equations of motion along the two dimensions, it is possible to find an expression for the time of flight of a projectile. In fact, we can use the following suvat equation for the vertical motion:

[tex]v_y = u_y -gt[/tex]

where

[tex]v_y[/tex] is the vertical velocity at time t

[tex]u_y = u sin \theta[/tex] is the initial vertical velocity, with

u = 83.0 m/s being the initial speed

[tex]\theta=62.0^{\circ}[/tex] being the angle of projection

The arrow reaches its maximum altitude when the vertical velocity becomes zero, so when

[tex]v_y = 0[/tex]

Which means that the equation becomes

[tex]0=u sin \theta - gt[/tex]

So, the time to reach the maximum altitude is

[tex]t=\frac{u sin \theta}{g}[/tex]

The time of flight is just twice the time needed to reach the maximum altitude, so:

[tex]T=2t=\frac{2u sin \theta}{g}[/tex]

And substituting the data for this arrow, we find:

[tex]T=\frac{2(83.0)(sin 62.0^{\circ})}{9.8}=15.0 s[/tex]

Learn more about projectile motion:

brainly.com/question/8751410

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Answer: 14.96

Explanation: