Answer:
0.01 H
Explanation:
V = 12 cos (1000t + 45) 
C = 100 micro farad
Let the inductance be L . 
When the current and the voltage are in the same phase so it is the condition of resonance. 
So capacitive reactance = inductive reactance 
Xc = XL 
1/ωC = ωL 
L = 1 / ω²C 
By comparisonV = Vo Cos (ωt + Ф)
ω = 1000 rad/s 
L = 1 / (1000 x 1000 x 100 x 10^-6) 
L = 1 / 100 
L = 0.01H
thus, the inductance of the inductor is 0.01 H. 
 
        
             
        
        
        
Answer:
a) transparent
b) transparent
c) opaque
Explanation:
In the first one, the light rays go completely through, so it is transparent.
The second one I'm not too sure about. It is refraction so it's going through a different material, but the fact that it went through makes me say transparent.
Last one, the light rays are reflecting off the surface so it's opaque.
Please feel free to correct me if I'm wrong. This is just my understanding 
 
        
                    
             
        
        
        
An aquifer is the most expected feature that is likely to be reach after drilling through the unsaturated zone. Aquifer has tendency to transform ground water to the surface through voids. The depth of aquifer varies. 
 
        
                    
             
        
        
        
Answer:
Explanation:
Amount of heat required can be found from the following relation 
Q = mcΔT
m is mass of the body , c is specific heat and ΔTis rise in temperature . 
Here m = 300 kg 
c = 3350 J /kg k 
ΔT = 30 - 25 
= 5 °C
Putting the values in the expression above 
Q = 300 x 3350 x 5 
= 5025000 J 
Rate at which energy is absorbed = 1200 J /s 
Time required
= 5025000 / 1200
= 4187.5 S 
= 69.8 minute
= 1 hour 9.8 mimutes.