True if you look up the question Is velocity speed in a certain direction you would’ve gotten the answer but I’m pretty sure it’s true
Answer:
(C). The line integral of the magnetic field around a closed loop
Explanation:
Faraday's law states that induced emf is directly proportional to the time rate of change of magnetic flux.
This can be written mathematically as;

is the rate of change of the magnetic flux through a surface bounded by the loop.
ΔФ = BA
where;
ΔФ is change in flux
B is the magnetic field
A is the area of the loop
Thus, according to Faraday's law of electric generators
∫BdL =
= EMF
Therefore, the line integral of the magnetic field around a closed loop is equal to the negative of the rate of change of the magnetic flux through the area enclosed by the loop.
The correct option is "C"
(C). The line integral of the magnetic field around a closed loop
Answer:
Angle of first order maximum, 
Explanation:
Given that,
Wavelength of the light, 
Number of lines, N = 8000 per cm
The relation between the number of lines and the slit width is given by :


The equation of grating is given by :

n = 1



So, the angle of the first-order maximum is 21.19 degrees. Hence, this is the required solution.
I'm pretty sure the answer would be D