Exercício: Dois vectores a e b têm módulos iguais a 10 unidades e são
orientados conforme mostra a figura ao lado. O vector soma
dos dois vectores é representado por r. Determine:
a) As componentes x e y do vector soma.
b) O módulo do Vector soma.
c) O ângulo que o vector soma forma com o eixo dos x.

The passing of heat through a material while the material itself stays in place. a. radiation b. conduction c. convection

What are similarities and differences of reflection, refraction, diffraction and absorption?

Antireflective coatings on solar cells are often made by applying a thin film of silicon nitride (sinx), which has an index of refractive of 1.2, on the top of the silicon solar cell, which has a refractive index of about 3.5. however, the sun emits radiation of various wavelengths which the solar cell absorbs, and the antireflective coating can only absolutely minimize the reflection of one of these wavelengths. the coating thickness is chosen to reduce the reflection of green/yellow light (e = 2.2 ev), which is the most intense color in the solar spectrum (shown below). which of the following coatings would minimize reflection of green/yellow light? the answer is 820 nm how? what is the angular width of the central maximum of an electron traveling at 2 x 108 m/s going through a single slit of width 1 mm.