(a) 
The relationship between frequency and wavelength of an electromagnetic wave is given by
where
is the speed of light
is the frequency
is the wavelength
In this problem, we are considering light with wavelength of
Substituting into the equation and re-arranging it, we can find the corresponding frequency:
(b) 
The period of a wave is equal to the reciprocal of the frequency:
And using 
as we found in the previous part, we can find the period of this wave:
Answer:9A
Explanation:
let the last wire be wire C
According to Kirchhoff's rule
the sum of all currents entering a junction must be equal to the sum of all currents leaving a junction
Ic=Ia+Ib
Ic= 4+5
Ic=9A
Number 20 is B and 21 is C
Answer:
The initial velocity of the ball is 28.714 m/s
Explanation:
Given;
time of flight of the ball, t = 2.93 s
acceleration due to gravity, g = 9.8 m/s²
initial velocity of the ball, u = ?
The initial velocity of the ball is given by;
v = u + (-g)t
where;
v is the final speed of the ball at the given time, = 0
g is negative because of upward motion
0 = u -gt
u = gt
u = (9.8 x 2.93)
u = 28.714 m/s
Therefore, the initial velocity of the ball is 28.714 m/s
Answer:
The answer to your question is: mass = 38.93 kg
Explanation:
Data
mass = ?
Weight = 382 N
gravity = 9.81 m/s2
Formula
Weight = mass x gravity
mass = weight / gravity
mass = 382 / 9.81 substitution
mass = 38.93 kg result
