at the top most point if Rupert will not fall then normal force at the top point is almost zero for minimum speed
so here we can say

now if





so above will be the minimum speed
Given that,
Current = 4 A
Sides of triangle = 50.0 cm, 120 cm and 130 cm
Magnetic field = 75.0 mT
Distance = 130 cm
We need to calculate the angle α
Using cosine law




We need to calculate the angle β
Using cosine law




We need to calculate the force on 130 cm side
Using formula of force



We need to calculate the force on 120 cm side
Using formula of force


The direction of force is out of page.
We need to calculate the force on 50 cm side
Using formula of force


The direction of force is into page.
Hence, The magnitude of the magnetic force on each of the three sides of the loop are 0 N, 0.1385 N and 0.1385 N.
Answer:
D.
Explanation:
To solve the problem it is necessary to apply the concepts of Destructive and constructive interference. The constructive interference in tin film is given by

Where,
t = thickness
Wavelenght
m= is an integer
n= film/refractive index
We use this equaton because phase change is only present for gasoline air interface, but not at the gasoline-water interface. <em>The minimum t only would be when the value of m=0 then</em>



Therefore the correct answer is D. The minimum thickness of the film to see ab right reflection is 100nm
Answer:
0.66 s
Explanation:
∆x = v∆t → 2 × 115 = 350 ∆t → ∆t = 230/350 = 0.66 s