Y₀ = initial position of the balloon at the top of the building = 44 m
Y = final position of the balloon at halfway down the building = 44/2 = 22 m
a = acceleration of the balloon = - 9.8 m/s²
v₀ = initial velocity of the balloon = 0 m/s
v = final velocity of the balloon = ?
using the kinematics equation
v² = v₀² + 2 a (Y - Y₀)
inserting the values
v² = 0² + 2 (- 9.8) (22 - 44)
v = 20.78 m/s
So we want to know the mechanical advantage of a machine that has 5 N input force and 25 N out force. Mechanical advantage Ma is the measure of force amplification of some machine. We calculate it by taking the ratio of the output force Fo over the input force Fi. Ma=Fo/Fi=(25 N)/(5 N)=5. So Mechanical advantage for our machine is Ma=5 and the correct answer is the second one.
In getting the magnitude of the induced emf in the coil as a function of time, the formula of it would be the length times the quotient of intensity of the distance and time travel times total intensity time total resistance. I think with that formula, you can get the magnitude of the induced emf.