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:
Speed is solved with time and distance but has no direction
Average velocity is solved with Δx/Δt and has a direction
Answer:
366 m
Explanation:
u = 90 km/h = 25 m/s,
theta = 5 degree
acceleration, a = g Sin theta = 9.8 x Sin 5 = 0.854 m/s^2
The final velocity os zero and let the braking distance be s.
Use third equation of motion
v^2 = u^2 - 2 a s
0 = 25 x 25 - 2 x 0.854 x s
s = 366 m
Answer here
The displacement of the cars is somewhere near 0 miles since they virtually finish where they started. Yet the successful cars have covered a distance of 500 miles