Same answer as the first one above
The 2nd Law says F=ma, where F is the force in Newtons, m is mass and a is acceleration. Earth's gravity is an acceleration, 9.8m/s^2. So you can solve the equation for mass, m=F/a, or m=F/9.8 where you've measured the force (weight) in Newtons.
Answer:
a) 1.2*10^{-3}cos(1.25t)
b) 0.49mV
Explanation:
a) The coil rotates periodically with period T. Hence, we can write the variation of the magnetic flux with a sinusoidal function, and with max flux NAB. Thus, we have that:

where we have used the values given by the information of the problem for N B and A.
b)
the emf is given by:

hope this helps!!