An object is falling from a height of d and reaches a final velocity of vf. Calculate velocity when the object has fallen a distance d/2.

The final velocity, , is gd.

Explanation:

The condition here is a free falling object. Thus from the third equation of motion under free fall, we have;

= + 2gs

where is the final velocity of the object, is the initial velocity of the object, g is the gravitational force and s is the height.

Since the object falls from a height of d, then = 0 m/s, and s = d.

So that;

= 0 + 2gd

   = 2gd

= 2gd

When the distance is , = 0 m/s.

Then;

= 2g

= g x d

When the object falls through the height , then the final velocity is gd.

work: w = fd (given)

work done by chet   =50*1 = 50 j

work done by mika =40*2 = 80 j

work done by sara =30*1.5 = 45 j

work done by bill =60*0.5 = 30 j

students in order from the greatest amount of work done to the least is mika> chet> sara> bill

hence option (b) is correct.

the earths atmosphere is made up of nitrogen and oxygen. solids can turn into gasses through a process called sublimation. sublimation is the transition of a substance directly from the solid to the gas phase, without passing through the intermediate liquid phase.

hope this : d