Answer:
a) Magnetic field strength, B = 2.397 * 10⁻⁷ T
b) Total energy density, U = 4.58 * 10⁻⁸ J/m³
c) Power flow per unit area, S = 13.71 W/m²
Explanation:
a) Electric field strength, E = 71.9 V/m
The relationship between the Electric field strength and the magnetic field strength in vacuum is:
E = Bc where c = 3.0 * 10⁸ m/s
71.9 = B * 3.0 * 10⁸
B = 71.9 / (3.0 * 10⁸)
B = 23.97 * 10⁻⁸
B = 2.397 * 10⁻⁷ T
b) Total Energy Density:
 
c)Power flow per unit area
 
 
        
             
        
        
        
Answer:
300 K 
Explanation:
First, we have find the specific heat capacity of the unknown substance. 
The heat gained by the substance is given by the formula:
H = m*c*(T2 - T1) 
Where m = mass of the substance 
c = specific heat capacity 
T2 = final temperature 
T1 = initial temperature 
From the question:
H = 200J
m = 4 kg
T1 = 200K
T2 = 240 K
Therefore:
200 = 4 * c * (240 - 200)
200 = 4 * c * 40
200 = 160 * c
c = 200/160
c = 1.25 J/kgK
The heat capacity of the substance is 1.25 J/kgK. 
If 300 J of heat is added, the new heat becomes 500 J. 
Hence, we need to find the final temperature, T2, when heat is 500 J. 
Using the same formula:
500 = 4 * 1.25 * (T2 - 200)
500 = 5 * (T2 - 200)
100 = T2 - 200
=> T2 = 100 + 200 = 300 K
The new final temperature of the unknown substance is 300K.
 
        
             
        
        
        
The non-relativistic formula for kinetic energy for low speeds is :
K.E = 0.5mv^2 = 0.5 * 22 * (5)^2 = 275 J
        
                    
             
        
        
        
Sattelites don't need any fuel to stay in orbit. The applicable law is...."objects in motion tend to stay in motion". Having reached orbital velocity, any such object is essentially "falling" around the earth. Since there is no (or at least very little) friction in the vacuum of space, the object does not slow.... It simply continues. 
Sattelites in "low" earth orbit do encounter some friction from the very thin upper atmosphere, and they will eventually "decay".
:)