Answer:
The minimum magnetic field is 0.078 T.
Explanation:
Given that,
Current = 16 A
Side = 15 cm
Mass 
Mass each segment in given square loop is

We need to calculate the torque due to gravity
Using formula of torque


The torque due to magnetic field


The equilibrium condition

Put the value into the formula



Put the value into the formula


Hence, The minimum magnetic field is 0.078 T.
Yup the correct answer is A jus finished the quiz :)
hope i helped^_^
Answer
given,
mass of the piano = 170 kg
angle of the inclination = 20°
moves with constant velocity hence acceleration = 0 m/s²
neglecting friction
so, force required to pull the piano
F = m g sin θ
F = 170 × 9.81 × sin 20°
F = 570.39 N
so, force required by the man to push the piano is F = 570.39 N
Yes, in general, metalloids are slightly reactive.