An autographed baseball rolls off of a 0.76 m high desk and strikes the floor 0.61 m away from the desk. how fast was it rolling on the desk before it fell off? the acceleration of gravity is 9.81 m/s 2 . answer in units of m/s.

d = distance = 0.76 m 
a = acceleration due to gravity = 9.81 m/s^2
u = initial velocity = 0 (as the ball rolls off the table the vertical velocity = 0 
t = time = missing so we need to solve it 

So we use the equation d = ut + 1/2 at², and ever since u is zero, ut is zero and the equation becomes to d = 1/2 at² and this reorders to t = sqrt (2d/a) = 0.39 seconds. 

Since there are no forces performing in the horizontal direction, this means that there is no acceleration in the horizontal direction and consequently the horizontal velocity is persistent.

Velocity = distance/ time.

Horizontal velocity is therefore horizontal distance/time = 0.61 m/0.39s = 1.56 m/s.

The autographed baseball rolled off at 1.564 m/s before it fell off.

Given the following data:

To find how fast the autographed baseball was rolling on the desk before it fell off:

First of all, we would use the second equation of motion to determine the time it took:

Where:

Substituting the given values into the formula, we have;

Time, t = 0.39 seconds.

Next, we would determine the horizontal speed:

Horizontal speed = 1.564 m/s

Therefore, the autographed baseball rolled off at 1.564 m/s before it fell off.

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