contestada

A supply bag is dropped from a rescue plane. After the bag falls for 3.2 seconds , what is the velocity of the bag?

Respuesta :

Answer: -31.36 m/s

Explanation:

This is a problem of motion in one direction (specifically vertical motion), and the equation that best fulfills this approach is:

[tex]V_{f}=V_{o}+a.t[/tex]  (1)

Where:

[tex]V_{f}[/tex] is the final velocity of the supply bag

[tex]V_{o}=0[/tex] is the initial velocity of the supply bag (we know it is zero because we are told it was "dropped", this means it goes to ground in free fall)

[tex]a=g=-9.8m/s^{2}[/tex] is the acceleration due gravity (the negtive sign indicates the gravity is downwards, in the direction of the center of the Earth)

[tex]t=3.2s[/tex] is the time

Knowing this, let's solve (1):

[tex]V_{f}=0+(-9.8m/s^{2})(3.2s)[/tex]  (2)

Finally:

[tex]V_{f}=-31.36m/s[/tex]  Note the negative sign is because the direction of the bag is downwards as well.