A plane dives at 43° to the horizontal and releases a package at an altitude of 360m. If the load is in the air for 6.4s, find: a)the speed of the plane when it released the package b) the horizontal distance traveled by the package after it is released.

Answer :

skyluke89

a) 36.5 m/s

The motion of the package along the vertical direction is a free fall motion, so we can use the following suvat equation:

[tex]s=u_y t + \frac{1}{2}gt^2[/tex]

where, chosing downward as positive direction:

s = 360 m is the vertical displacement of the package

[tex]u_y[/tex] is the initial vertical velocity of the package, which is equal to that of the plane

t = 6.4 s is the time of flight

[tex]g=9.8 m/s^2[/tex] is the acceleration of gravity

Solving for [tex]u_y[/tex], we find:

[tex]u_y = \frac{s}{t}-\frac{1}{2}gt=\frac{360}{6.4}-\frac{1}{2}(9.8)(6.4)=24.9 m/s[/tex]

The initial vertical velocity is related to the initial speed of the plane by

[tex]u_y = u sin \theta[/tex]

where

u is the initial speed of the plane

[tex]\theta=43^{\circ}[/tex]

Solving for u,

[tex]u=\frac{u_y}{sin \theta}=\frac{24.9}{sin 43}=36.5 m/s[/tex]

b) 170.9 m

The horizontal velocity of the package is given by

[tex]v_x = u cos \theta = (36.5)(cos 43)=26.7 m/s[/tex]

where

u = 36.5 m/s is the initial speed

[tex]\theta=43^{\circ}[/tex]

The horizontal velocity of the package is constant since there are no forces along this direction: therefore, the horizontal distance travelled by the package is given by

[tex]d=v_x t[/tex]

And substituting t = 6.4 s, we find

[tex]d=(26.7)(6.4)=170.9 m[/tex]

Other Questions