Answer:
Option D is correct: 170 µW/m²
Explanation:
Given that,
Frequency f = 800kHz
Distance d = 2.7km = 2700m
Electric field Eo = 0.36V/m
Intensity of radio signal
The intensity of radial signal is given as
I = c•εo•Eo²/2
Where c is speed of light
c = 3×10^8m/s
εo = 8.85 × 10^-12 C²/Nm²
I = 3×10^8 × 8.85×10^-12 × 0.36²/2
I = 1.72 × 10^-4W/m²
I = 172 × 10^-6 W/m²
I = 172 µW/m²
Then, the intensity of the radio wave at that point is approximately 170 µW/m²
The elastic potential energy stored in the car's spring during the process is 3.75 J
<h3>Determination of the spring constant</h3>
From the question given above, the following data were obtained:
K = F/e
K = 15 / 0.5
K = 30 N/m
<h3>Determination of the potential energy</h3>
- Spring constant (K) = 30 N/m
PE = ½Ke²
PE = ½ × 30 × 0.5²
PE = 15 × 0.25
PE = 3.75 J
Therefore, the elastic potential energy stored in the car's spring during the process is 3.75 J
Learn more about energy stored in spring:
brainly.com/question/4280346
Answer: momentum has the same direction as that of velocity but when 2 bodies with the same linear momentum & different velocities it has different masses because a vector quantity is represented by a cross product of mass and velocity of object .
In this problem, we apply the equation regarding kinematics expressed as vf^2 = v0^2 + 2as vf eventually becomes zero because the ball stops in the end. a = -9.8 m/s2s = 2 metres this time
This gives initial velocity, vo equal to 6.26m/s
now 6.26-(-8.85) = 15.11m/s
change in velocity/change in time = average acceleration 15.11/(12/1000) = 1259.167 m/s^2
