The tension in the string an instant before it broke is; T = 0.86 N
We are given;
mass of ball; m = 60 g = 0.06 kg
Length of string; L = 70 cm = 0.7 m
Height the ball reaches; h = 150 cm = 1.5 m
From Newton's equation of motion;
v² - u² = 2as
where v = 0 m/s Thus;
-u² = 2(-9.81 * (1.5 - 0.7)
u² = 15.696
u = √15.696
u = 3.17 m/s
Thus, tension is;
T = mu²/L
T = (0.06 * 3.17²)/0.7
T = 0.86 N
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