What does "from rest" mean to you?
It is impossible to answer the question without know what you mean by "y"? If it is the height above the floor then obviously "hitting the floor" means y= 0. Set y equal to 0 and solve for t.
A ball is dropped from rest from a height h. Neglecting air resistance and taking the acceleration due to gravity to be g, calculate how ling it takes to hit the floor in terms of g and h.
so i set up two equations of motion.
there is not motion in the x direction so
so integrating twice i get two equations
not sure where to go from here, any help appreciated, how do i work out the constants on integration ? I know the ball is dropped from rest, so one of the constants will be 0?
What does "from rest" mean to you?
It is impossible to answer the question without know what you mean by "y"? If it is the height above the floor then obviously "hitting the floor" means y= 0. Set y equal to 0 and solve for t.
You have \frac{dy}{dt}=0 when t=0 ("the ball is dropped from rest") and y=h when t=0 ("from a height h", assuming y=0 is the ground). These two conditions give you y_1 and y_0. You then have to solve y(t)=0 for t, which will be "how long it takes to hit the floor".
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