Answer:
The temperature rises by 0.52K
Explanation:
Detailed explanation and calculation is shown in the image below
Option (D) is the correct one.
In order to increase the amount of work done, we need to increase the force applied to the object.
Answer:
Part A
The intensity is
Part B
The intensity is 
Explanation:
From the question we are told that
The intensity of the light detected by first eye is 
Now at initial state according the question the light ray is perpendicular to the eye so it means that it is at 90° the eye
Now the first question is to obtain the intensity the first eye (the first in this case is the one focused on the light )would detect when the head is rotated by 20° its previous orientation
This is mathematically evaluated as

Now the second question is to obtain the intensity the first eye (the first eye in this case is the one that is not focused on the light )would detect when the head is rotated by 20° its previous orientation
Now in this case the angle between the eye and the light is 90-20 = 70°
So


Answer: The correct answer is B
Explanation: The string is pulling right and the string is unraveling causing it to accelerate left
Gravity is a non contact force , jump from a little high place (don't do that :P) , you wont just get stuck in the air you will fall down , this is gravity you dont need any contact