Question

What is the maximum velocity that a 0.3–kilogram mass attached to a 0.75–meter string can have if the mass is whirled around in a circular horizontal path? The maximum tension that the string can withstand is 250 newtons.
375 meters/second

22.4 meters/second

19.4 meters/second

25 meters/second

Answer 1

$f \: = \: \frac{m {v}^{2} }{r} \\ {v}^{2} \: = \: \frac{fr}{m} \\ v \: = \: \sqrt{ \frac{fr}{m} }$
f = 250 N
r = 0.75 m
m = 0.3 kg
$v \: = \: \sqrt{ \frac{250 \: \times \: 0.75}{0.3} } \: \frac{m}{s}$
v = 25 m/s.
Hence, Maximum Velocity = v = 25 m/s
D) 25 m/s.