Answer:
799.54 ft
Explanation:
Linear thermal expansion is:
ΔL = α L₀ ΔT
where ΔL is the change in length,
α is the linear thermal expansion coefficient,
L₀ is the original length,
and ΔT is the change in temperature.
Given:
α = 1.2×10⁻⁵ / °C
L₀ = 800 ft
ΔT = -17°C − 31°C = -48°C
Find: ΔL
ΔL = (1.2×10⁻⁵ / °C) (800 ft) (-48°C)
ΔL = -0.4608
Rounded to two significant figures, the change in length is -0.46 ft.
Therefore, the final length is approximately 800 ft − 0.46 ft = 799.54 ft.
Answer:
Angle of incidence = 20°
Angle of reflection = 20°
Explanation:
Applying,
The first Law of Refraction: The incident ray, the reflected ray and the normal at the point of incidence all lies in the plane.
From the diagram,
Angle of incidence = 90-70
Angle of incidence = 20°
From the law of reflection,
Angle of incidence = Angle of reflection
Therefore,
Angle of reflection = 20°
The Electromagnetic spectrum.
Sorry to say but I know that t(e introduction is first and the coda is last
