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Giddy UP!!!!!!!!!!!!!!!!!!!!!
21. light changes its direction when travelling through a new medium because denser mediums have a higher angle of refraction.
Answer:
option (E) is correct.
Explanation:
Work done is defined as the product of force and the distance in the direction of force.
force, f = 100 N
Coefficient of friction, = 0.25
distance = 15 m
So, net force F = f - friction force
F = 100 - 0.25 x m g
Work = (100 - 0.25 mg) x d cosθ
For minimum work, the angle should be maximum.
So, the value of θ is 76°.
thus, option (E) is correct.
Answer: A medium in which speed of light is more is known as optically rarer medium and a medium in which speed of light is less is said to be optically denser medium. For example in air and water, air is raer and water is a denser medium.
Explanation:
