Answer:
1341.03 V/m
Explanation:
The power output per unit area is the intensity and also the is the magnitude of the Poynting vector.
= cε₀
⇒ 
= cε₀
Where;
P is the power output
A is the area of the beam
c is speed of light
ε₀ is permittivity of free space 8.85 × 10⁻¹² F/m
is the average (rms) value of electric field
Making electricfield the subject of the equation
= P / Acε₀
= √(P / Acε₀)
But area A = πr²
= √(P / πr²cε₀)
Given:
Output power, P = 15 mW = 0. 015 W
Diameter, d = 2 mm = 0.002 m
⇒ Radius, 
Solving for average (rms) value of electric field;
= 1341.03 V/m
Answer:
Option B. 2.8 s
Explanation:
The following data were obtained from the question:
Initial velocity (u) = 27 m/s
Angle of projection (θ) = 30
Acceleration due to gravity (g) = 9.8 m/s²
Time of flight (T) =?
The time of flight of the ball can be obtained as follow:
T = 2uSineθ / g
T = 2 × 27 × Sine 30 / 9.8
T = 2 × 27 × 0.5 / 9.8
T = 27 / 9.8
T = 2.8 s
Therefore, time of flight of the ball is 2.8 s
Answer:
Associations Clusters
Explanation:
There is three basic type of clusters, globular clusters, open clusters, associations clusters. Associations cluster consist of younger stars that is younger than globular and open clusters stars.
Answer: Wave speed may equal frequency*wavelength. Yet doubling the frequency only halves the wavelength; wave speed remains the same. To change the wave speed, the medium would have to be changed. 24. What are some simple steps I can take to protect my privacy online? Many people ... So if you double the frequency and keep the speed constant, the wavelength halves to give the same speed with the doubled frequency. 3.8k views ... The period of a note is 0.3 seconds and the speed of sound in air is 340 m/s. So if you double the frequency and keep the speed constant, the wavelength halves to give the same speed with the doubled frequency. What is the period of a wave if the wavelength is 100m and the speed is 200 m/s? ... If you move towards a light source, the wavelength decreases.
Explanation:
Answer:
<h3>62.5N</h3>
Explanation:
The pressure at one end of the piston is equal to the pressure on the second piston.
Pressure = Force/Area
F1/A1 = F2/A2
Given
F1 = 250N
A1 = 2.0m²
A2 = 0.5m²
F2 = ?
Substituting the given values in the formula;
250/2 = F2/0.5
cross multiply
250*0.5 = 2F2
125 = 2F2
F2 = 125/2
F2 = 62.5N
Hence the force needed to lift this piston if the area of the second piston is 0.5 m^2 is 62.5N
