All machines are not 100% efficient because of <span>C. Friction</span>
Answer:
Light refracts when its speed changes as it enters a new medium.
Explanation:
Bending of light wave while it entering a medium with different speed is called refraction of light. Light passing from a faster medium to the slower medium bends the light rays toward the normal to boundary between two media. The amount of the bending of light depends on refractive index of the two media which is described by the Snell's Law. The angle of incidence is not equal to angle of refraction. Rainbow is caused but this refraction phenomena. Also Refraction is used in magnifying glasses, prism and lenses
The final speed of the nickel at the given quantity of heat is determined as 202.1 m/s.
<h3>Final speed of the nickel</h3>
Apply the principle of conservation of energy.
Q = mcΔθ
Q = (18)(0.444)(66 - 20)
Q = 367.63 J
Q = K.E = ¹/₂mv²
2K.E = mv²
v = √(2K.E/m)
where;
v = √(2 x 367.63)/(0.018))
v = 202.1 m/s
Learn more about speed here: brainly.com/question/4931057
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