Either theory or evidence
Answer:
EMF induced in the loop is 9.4 V
Explanation:
As we know that initial magnetic flux of the loop is given as



As soon as the area of the loop becomes zero the final magnetic flux of the loop is ZERO
Now as per faraday's law of electromagnetic induction the EMF is induced due to rate of change in magnetic flux
so we will have

so we will have


Given required solution
M=10kg W=? W=Fd
v=5.0m/s F=mg
t=2.40s =10*10=100N
S=VT
=5m/s*2.4s
=12m
so W=12*100
W=1200J
Answer:
Electric field, E = 45.19 N/C
Explanation:
It is given that,
Surface charge density of first surface, 
Surface charge density of second surface, 
The electric field at a point between the two surfaces is given by :



E = 45.19 N/C
So, the magnitude of the electric field at a point between the two surfaces is 45.19 N/C. Hence, this is the required solution.
Answer:
the magnitude of the electric field is 1.25 N/C
Explanation:
The induced emf in the cube ε = LB.v where B = magnitude of electric field = 5 T , L = length of side of cube = 1 cm = 0.01 m and v = velocity of cube = 1 m/s
ε = LB.v = 0.01 m × 5 T × 1 m/s = 0.05 V
Also, induced emf in the cube ε = ∫E.ds around the loop of the cube where E = electric field in metal cube
ε = ∫E.ds
ε = Eds since E is always parallel to the side of the cube
= E∫ds ∫ds = 4L since we have 4 sides
= E(4L)
= 4EL
So,4EL = 0.05 V
E = 0.05 V/4L
= 0.05 V/(4 × 0.01 m)
= 0.05 V/0.04 m
= 1.25 V/m
= 1.25 N/C
So, the magnitude of the electric field is 1.25 N/C