I need help with these and explanations why. Thanks A massless meter stick is fr
ID: 1475025 • Letter: I
Question
I need help with these and explanations why. Thanks
A massless meter stick is free to rotate about a frictionless pin at the 30-cm mark. Attached to the end of the meter stick at the zero cm mark is an 800-gram mass labeled m_1, and a 400-gram m_2 is attached to the 90 cm mark. If the meter-stick system is in the horizontal position as shown, is the magnitude of the torque about the pivot pin by the mass m_1 greater than, less than, or equal to the magnitude of the torque by mass m_2? If the meter-stick system is in the horizontal position but rotated 180 degree as shown above, is the magnitude of the torque about the pivot pin by the mass m_1 greater than, less than, on equal to the magnitude of the torque by mass m_2? Explain.Explanation / Answer
(1)m1 =800g , m2 =400g
d1 = 30 cm , d2 =L-d1 =90 - 30 =60 cm
Torque T =rXF
Torque due to m1 is T1= d1*m1g = (0.3*0.8*9.8)
T1 =2.352 N.m
Torque due to m2 is T2= d2*m2g = (0.6*0.4*9.8)
T2 =2.352 N.m
T1 =T2
Correct option is (c)
(2)
Torque T =rXF
Torque due to m1 is T1= d1*m1g = (0.3*0.8*9.8)
T1 =2.352 N.m
Torque due to m2 is T2= d2*m2g = (0.6*0.4*9.8)
T2 =2.352 N.m
T1 =T2
correct option is (c)