Answer:
Turns of the primary coil: 500
Current in the primary coil: Ip= 0.01168A
Explanation:
Considering an ideal transformer I can propose the following equations:
Vp×Ip=Vs×Is
Vp= primary voltaje
Ip= primary current
Vs= secondary voltaje
Is= secondary current
Np×Vs=Ns×Vp
Np= turns of primary coil
Ns= turns of secondary coil
From these equations I can clear the number of turns of the primary coil:
Np= (Ns×Vp)/Vp = (20×120V)/4.8V = 500 turns
To determine the current in the secondary coil I use the following equation:
Is= (1.4W)/4.8V = 0.292A
Therefore I can determine the current in the primary coil with the following equation:
Ip= (Vs×Is)/Vp = (4.8V×0.292A)/120V = 0.01168A
Answer:
12.0 V
Explanation:
Data :
Potential difference due to a single charge (+Q), E = 3.0 V
The Electric potential for the system of charges is given as:
![E=\frac{1}{4\pi \epsilon_o}[\Sigma\frac{Q}{r}]](https://tex.z-dn.net/?f=E%3D%5Cfrac%7B1%7D%7B4%5Cpi%20%5Cepsilon_o%7D%5B%5CSigma%5Cfrac%7BQ%7D%7Br%7D%5D)
for single charge, E = 3.0 V =
->eq(1)
And for 4 charges:
-eq(2)
from eq(1) and (2) we have
E = 4 × 3.0 V = 12 V
Explanation:
We need to calculate the time it had travelled first:
9:00 to 12:00 = 3 hours.
12:00 to 2:00 = 2 hours
Total travel time = 5 hours.
The formula for speed is distance ÷ time (Hence, the unit for speed is m/s, kph, mph, etc.)
= 629km ÷ 5 hours
= 125.8 km/hour ~ 125.8kph
I think it is D.) “Cycles around” but I am not positive.