Question

The top of the pool table is 0.810 m from the floor. the placement of the tape is such that 0 m is aligned with the edge of the table (as shown). the winner of the competition wants to know if he has broken the world record for the break shot of 32 mph (about 14.3 m/s). if the winner\'s ball landed a distance 4.65 m from the table edge, calculate his break shot speed.

Answer 1

Compute first for the vertical motion, the formula is:

y = gt²/2 

0.810 m = (9.81 m/s²)(t)²/2 

t = 0.4064 s 


whereas the horizontal motion is computed by: 

x = (vx)t 

4.65 m = (vx)(0.4064 s) 

4.65 m/ 0.4064s = (vx)

(vx) = 11.44 m / s
So look for the final vertical speed. 

(vy) = gt 

(vy) = (9.81 m/s²)(0.4064 s) 

(vy) = 3.99 m/s 


speed with which it hit the ground: 

v = sqrt[(vx)² + (vy)²] 

v = sqrt[(11.44 m/s)² + (3.99 m/s)²] 

v = 12.12 m / s