A ball of mass 50
kg and a speed of 5 m/s moves from the position q
= 00 to q
= 300.
Evaluate the rate at which the ball's speed is decreasing at the
position
q = 300.
a. 3.95 m/s2
b. 3.35 m/s2
c. 3.60 m/s2
d. 3.00 m/s2
an = v2/r
= 52/5
= 5 m/s2
Consider the forces
acting on the ball in the horizontal and vertical directions
T sin q + m an sin q
= m at cos q
T cos q
+ m an
cos q
+ m at
sin q
= mg
=> 0.5 T + 125 = 43.3 at
---------- (1)
and 0.866 T + 25 at
= 490.5 - 216.5 = 274 ---------(2)
Solving (1) and (2), we have at = 3.35 m/s2
The
rate at which the ball's speed is decreasing at
q = 300
is 3.35 m/s2