Explanation:
velocity is distance divided by time.
so
the average speed of the ball is 10m/20s
= 0.5 m/s
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: 24.7 km/h
Explanation:
1) Average speed definition and formula
The average speed is the total distance run divided by the time elapsed:
S = distance / time
2) Distance 1 = 67 km
3) Distance 2 = 81 km
4) Total distance traveled = 67 km + 81 km = 148 km
5) time 1 = 1 hour
6) time 2 = 5 hours
7) total time = time 1 + time 2 = 1 h + 5 h = 6 h
8) Average speed:
S = 148 km / 6 h = 24.7 km/h
You're going to use the constant acceleration motion equation for velocity and displacement:
(V)final²=(V)initial²+2a(Δx)
Given:
a=0.500m/s²
Δx=4.75m
(V)intial=0m
(V)final= UNKNOWN
(V)final= 2.179m/s