Answer:
Explanation:
In the four hours before 13:00 the train traveled 4(80) = 320 km.
It needs to travel another 4(320) = 1280 km in the next 21:00 - 13:00 = 8 hrs.
1280 / 8 = 160 km/hr
Answer;
A barrier, a surface or a boundary
Explanation;
Reflection is the property waves that occurs due to the bouncing back of a wave after it strikes a barrier.
Reflection involves change in direction of a wavefront at an interface between two different media such that the wavefront returns into the medium from which it originated. In other words, the direction of the wave changes when they bounce of a barrier or a surface.
Capillarity "Capillarity causes the part of the surface of a liquid in contact with a solid, to be either elevated above (e.g. water), or depressed below (e.g. mercury), the rest of the surface. This trait is named for the behaviour of liquids in capillary tubes placed perpendicular to the surface. The forces operating within capillarity are cohesion, adhesion, and surface tension."
Answer:
λ = 605.80 nm
Explanation:
These double-slit experiments the equation for constructive interference is
d sin θ = m λ
where d is the distance between the slits, λ the wavelength of light and m an integer that determines the order of interference.
In this case, the distance between the slits is d = 1.11 mm = 1.11 10⁻³ m, the distance to the screen is L = 8.63 m, the range number m = 10 and ay = 4.71 cm
Let's use trigonometry to find the angle
tan θ = y / L
as the angles are very small
tan θ = sin θ / cos θ = sin θ
we substitute
sin θ = y / L
we substitute in the first equation
d y / L = m λ
λ = d y / m L
let's calculate
λ = 1.11 10⁻³ 4.71 10⁻²/ (10 8.63)
λ = 6.05805 10⁻⁷ m
let's reduce to nm
λ = 6.05805 10⁻⁷ m (10⁹ nm / 1m)
λ = 605.80 nm
The correct answer would be D. In an isolated system, the total amount of matter is conserved. This is in agreement with the law of conservation of mass where mass cannot be created or destroyed, what goes inside the process should be the same amount as what goes out the process.
