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Imagine a rock is dropped from the top of a tall building. After 2 seconds of falling, the rock’s instantaneous speed is approximately 20m/s. does anyone know is it true or false

Respuesta :

dvdkim19
True
It's in free fall( 9.8 m/s), 2 seconds have passed.

Answer:

TRUE

Explanation:

As we know that stone is falling freely from rest

so here we can use kinematics to find the final speed of the stone

[tex]v_f = v_i + at[/tex]

here we know that

[tex]v_i = 0[/tex]

[tex]a = 9.81 m/s^2[/tex]

[tex]t = 2 s[/tex]

now we have

[tex]v_f = 0 + (9.81)(2)[/tex]

[tex]v_f = 19.62 m/s[/tex]

so final speed of the rock is nearly 20 m/s

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