# Physics

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a) While painting a 12 meter high roof you knock the paint brush off the edge, with no air resistance on the brush how long will it take to hit the ground?
b) What would the velocity of the brush be before it hit the ground?

• Physics -

*While painting on a 12 meter high roof,

• Physics -

12m= (0m/s)+1/2(9.81m/s^2)(t^2)
12m= 0+(4.905m/s^2)(t^2)
t^2=12/4.905m/s^2
t^2= 2.45s^2
t= 1.565 s
t= 1.6 s

• Physics -

Velocity
12/1.6 sec= 7.5 meters/sec down

• Physics -

t= 1.565 s - correct
v =g•t =9.8•1.565 = 15.3 m/s

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