Answer:
The direction of the displacement is in North-West.
Explanation:
Resultant displacement D is
Here the direction is

Then the direction is
North-west.
20 N north because He is pushing it 20 newtons north.
Answer:
The Balmer series refers to the spectral lines of hydrogen, associated to the emission of photons when an electron in the hydrogen atom jumps from a level
to the level
.
The wavelength associated to each spectral line of the Balmer series is given by:

where
is the Rydberg constant for hydrogen, and where
is the initial level of the electron that jumps to the level n = 2.
The first few spectral lines associated to this series are withing the visible part of the electromagnetic spectrum, and their wavelengths are:
656 nm (red, corresponding to the transition
)
486 nm (green,
)
434 nm (blue,
)
410 nm (violet,
)
All the following lines lie in the ultraviolet part of the spectrum. The limit of the Balmer series, corresponding to the transition
, is at 364.6 nm.
Answer:
52
Explanation:
Tellurium is the element of the periodic table with atomic number 52.
The atomic number of a chemical element represents the number of atoms contained in the nucleus of the atom: therefore, this means that an atom of tellurium contains exactly 52 protons in its nucleus.
Tellurium is classified as a metalloid, having properties in between metals and non-metals, and it appears with a silver color.
Answer:
~The slope of the line on a velocity vs. time graph represents acceleration.
Explanation:
~~Acceleration is equal to the ratio between the change in velocity of an object and the time taken:
a=\frac{\Delta v}{\Delta t}a=
Δt
Δv
On a velocity-time graph, this ratio corresponds to the slope of the line. In fact, \Delta vΔv corresponds to the increment in the y-value (the velocity), while \Delta tΔt corresponds to the increment in the x-value (the time), therefore their ratio corresponds to the definition of slope of the line.