Lucite has a refractive index of n=1.50. This means that the speed of the light in lucite is decreased according to:

where

is the speed of light in air. Putting the number in the formula, we find that the speed of light in lucite is

The frequency of the light is

, so now we can calculate the wavelength in lucite by using the formula:

<span>Therefore, the correct answer is (2) 393 nm.</span>
Henry will lift 200 N load 20 m up a ladder in 40 s. While the Ricardo will take 400 N load in 80 seconds. So, For Henry to take 400 N load it will take him 80 seconds in two attempts. And,also, he will have to cover 40 m of distance.
Answer:
The current is changing at the rate of 0.20 A/s
Explanation:
Given;
inductance of the inductor, L = 5.0-H
current in the inductor, I = 3.0 A
Energy stored in the inductor at the given instant, E = 3.0 J/s
The energy stored in inductor is given as;
E = ¹/₂LI²
E = ¹/₂(5)(3)²
E = 22.5 J/s
This energy is increased by 3.0 J/s
E = 22.5 J/s + 3.0 J/s = 25.5 J/s
Determine the new current at this given energy;
25.5 = ¹/₂LI²
25.5 = ¹/₂(5)(I²)
25.5 = 2.5I²
I² = 25.5 / 2.5
I² = 10.2
I = √10.2
I = 3.194 A/s
The rate at which the current is changing is the difference between the final current and the initial current in the inductor.
= 3.194 A/s - 3.0 A/s
= 0.194 A/s
≅0.20 A/s
Therefore, the current is changing at the rate of 0.20 A/s.
Given :
Displacement , y = 0.75 m .
Angular acceleration ,
.
Initial angular velocity ,
.
To Find :
The value of vertical velocity after time t = 0.25 s .
Solution :
By equation of circular motion is given by :

Putting all given values we get :

Now , vertical velocity is given by :

Therefore , the numerical value of the vertical velocity of the car at time t=0.25 s is 4.90 m/s .
Hence , this is the required solution .
That prediction is not correct because Xenon is extremely stable; column 18 of the periodic table contains the noble gasses, which are stable because their outer-most energy levels are completely filled. Having the octet (8) of valence electrons means that the element no longer needs to lose or gain electrons to gain stability.
The column 17 elements are unstable because they only have one valence electron short of the stable octet configuration of the noble gasses.