A, Mechanical and A, Chemical.
Answer:
Explanation:
<u>1. Name of the variables:</u>

<u>2. Formulae:</u>




<u>3. Solution (calculations)</u>




Answer:
Induced emf, 
Explanation:
Given that,
Length of the helicopter, l = 4 m
Angular speed of the helicopter, 
The vertical component of the Earth’s magnetic field is, 
We need to find the induced emf between the tip of a blade and the hub. The induced emf in terms of angular velocity of an rotating object is given by :



So, the induced emf between the tip of a blade and the hub is
. Hence, this is the required solution.