Efficiency is completing a task as fast a possible the the least amount of effort.
Answer:
Magnitude of induced emf is 0.00635 V
Explanation:
Radius of circular loop r = 45 mm = 0.045 m
Area of circular loop 

Magnetic field is increases from 250 mT to 350 mT
Therefore change in magnetic field 
Emf induced is given by


Magnitude of induced emf is equal to 0.00635 V
Answer:
KE = 1.75 J
Explanation:
given,
mass of ball, m₁ = 300 g = 0.3 Kg
mass of ball 2, m₂ = 600 g = 0.6 Kg
length of the rod = 40 cm = 0.4 m
Angular speed = 100 rpm= 
=10.47\ rad/s
now, finding the position of center of mass of the system
r₁ + r₂ = 0.4 m.....(1)
equating momentum about center of mass
m₁r₁ = m₂ r₂
0.3 x r₁ = 0.6 r₂
r₁ = 2 r₂
Putting value in equation 1
2 r₂ + r₂ = 0.4
r₂ = 0.4/3
r₁ = 0.8/3
now, calculation of rotational energy




KE = 1.75 J
the rotational kinetic energy is equal to 1.75 J
The energy added here is potential energy since it is moving upward 180 meters in a gravitational field. This is then turned into KE when it rolls down. 2524N x 180m = 454,320J