Velocity, because if an object is in motion with no direction we will consider it as speed, but if it has direction we will consider it as Velocity. Hope it helps
Answer:
Electromagnetic wave are waves formed as a result of the oscillatory activities involving the electric and the magnetic field.
However in an Electromagnetic wave, the electric field and magnetic field carry equal amounts of energy and the magnitude of the electric field is directly proportional to the magnitude of the magnetic field. This direct proportionality gives rise to the speed of light being the constant between the two fields.
When the electric field is doubled then an equal action is to be set for the magnetic field so it doesn’t deviate from its main functions and characteristics.
Answer:
A. 2.82 eV
B. 439nm
C. 59.5 angstroms
Explanation:
A. To calculate the energy of the photon emitted you use the following formula:
(1)
n1: final state = 5
n2: initial state = 2
Where the energy is electron volts. You replace the values of n1 and n2 in the equation (1):

B. The energy of the emitted photon is given by the following formula:
(2)
h: Planck's constant = 6.62*10^{-34} kgm^2/s
c: speed of light = 3*10^8 m/s
λ: wavelength of the photon
You first convert the energy from eV to J:

Next, you use the equation (2) and solve for λ:

C. The radius of the orbit is given by:
(3)
where ao is the Bohr's radius = 2.380 Angstroms
You use the equation (3) with n=5:

hence, the radius of the atom in its 5-th state is 59.5 anstrongs
Answer: A
Explanation: isotopes of the same thing element have the same number of protons in the nucleus but differ in the number of neutrons.