Answer:
Part a)

Part b)

Part c)

Explanation:
Part a)
As we know that the speed of light is given as


now the frequency of the light is given as

so we have


Part b)
Position of Nth maximum intensity on the screen is given as

so here we know for 3rd order maximum intensity

n = 3
L = 1.4 m


Part c)
angle of third order maximum is given as



Answer:9.34 A/s
Explanation:
Given
radius of solenoid 
Emf induced 
no of turns per meter n=450
we know Induced EMF is given by

Magnetic Field is given by

thus 
Area of cross-section
where
solving integration we get

where r=distance from axis
R=radius of Solenoid



Answer:
(a) I_A=1/12ML²
(b) I_B=1/3ML²
Explanation:
We know that the moment of inertia of a rod of mass M and lenght L about its center is 1/12ML².
(a) If the rod is bent exactly at its center, the distance from every point of the rod to the axis doesn't change. Since the moment of inertia depends on the distance of every mass to this axis, the moment of inertia remains the same. In other words, I_A=1/12ML².
(b) The two ends and the point where the two segments meet form an isorrectangle triangle. So the distance between the ends d can be calculated using the Pythagorean Theorem:

Next, the point where the two segments meet, the midpoint of the line connecting the two ends of the rod, and an end of the rod form another rectangle triangle, so we can calculate the distance between the two axis x using Pythagorean Theorem again:

Finally, using the Parallel Axis Theorem, we calculate I_B:





//
I'm not really sure but I do know that it's not 0 because the object is still moving, even if it's only moving at 1 m/s.
We can’t see the attachment :(