Respuesta :

You have : 
------------- 

vf^2 - v0^2 = ( 2 ) ( -g ) ( yf - y0 ) 

vf^2 = vo^2 + ( 2 ) ( -g ) ( - 0.3 m ) 

vf^2 = ( 0.0 m/s )^2 + ( 2 ) ( - 9.807 m/s^2 ) (- 0.3 m ) 

vf^2 = 5.884 m^2 / s^2 

vf = ( 5.884 m^2 / s^2 )^1/2 

vf = - 2.43 m/s <-------------- [ minus sign since moving downward ]

The impact speed of the cup is 2.43 m/s.

What is mechanical energy?

The mechanical energy is the sum of kinetic energy and the potential energy of an object at any instant of time.

M.E = KE +PE

Given,  a cup falls off of a table from a height of 0.3 m.

Kinetic energy = Potential energy

1/2 mv² =mgh

The velocity at the bottom, when falling from the height h = 0.3m is

v= √2gh

Plug the values, we get

v = √(2 x 9.8 x 0.3)

v = 2.43 m/s

Thus, impact speed of the cup is 2.43 m/s.

Learn more about mechanical energy.

https://brainly.com/question/13552918

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