Answer:
See answer
Explanation:
The area of the circular loop is given by:

The magnetic flux is given by:

is parallel to
and
is constant in magnitude and direction therefore:

Part A)
initially the flux is 
after the interval
the flux is

now, the EMF is defined as:
,
if we consider
very small then we can re-write it as:

then:
![\epsilon =- \frac{-0.12}{0.0024} = 50 [V]](https://tex.z-dn.net/?f=%5Cepsilon%20%3D-%20%5Cfrac%7B-0.12%7D%7B0.0024%7D%20%3D%2050%20%5BV%5D)
Part B)
When looked down from above, the current flows counter clockwise, according to the right hand rule, if you place your thumb upwards (the direction of the magnetic field) and close your fingers, then the current will flow in the direction of your fingers.
Answer:
F = 1.047 10⁻² N
Explanation:
Let's use kinematics to find the angular acceleration
w = w₀ + α t
as for rest w₀ = 0
w = α t
α = w / t
let's reduce the magnitudes to the SI system
w = 1000 rev / min (2π rad/ 1 rev) (1 min/ 60s) = 104.72 rad / s
m = 1.00 g (1 kg / 1000 g) = 1,000 10⁻³ kg
r = 10.0 cm (1 m / 100 cm) = 0.100 m
let's calculate
α = 104.72 / 1
α = 104.72 rad / s²
angular and linear variables are related
a = α r
a = 104.72 0.100
a = 10.47 m / s²
finally we substitute in Newton's second law
F = 1 10⁻³ 10.47
F = 1.047 10⁻² N