1. 
Explanation:
We have:
voltage in the primary coil
voltage in the secondary coil
The efficiency of the transformer is 100%: this means that the power in the primary coil and in the secondary coil are equal

where I1 and I2 are the currents in the two coils. Re-arranging the equation, we find

which means that the current in the secondary coil is 14% of the value of the current in the primary coil.
2. 5.7 V
We can solve the problem by using the transformer equation:

where:
Np = 400 is the number of turns in the primary coil
Ns = 19 is the number of turns in the secondary coil
Vp = 120 V is the voltage in the primary coil
Vs = ? is the voltage in the secondary coil
Re-arranging the formula and substituting the numbers, we find:

Answer:
The observable universe is still huge, but it has limits. because it's most likely like an plane all round.
Explanation:
Density is given by:
D = M/V
D = density, M = mass, V = volume
Given values:
M = 3.7g, V = 4.6cm³
Plug in and solve for D:
D = 3.7/4.6
D = 0.80g/cm³
Answer:
f = 1 m
Explanation:
The magnification of the lens is given by the formula:

where,
M = Magnification = 4
q = image distance = 5 m
p = object distance = ?
Therefore,

Now using thin lens formula:

<u>f = 1 m</u>
The Earth’s average orbital speed expressed in kilometers per hours is 107225.5 Km/hr and the mass of the sun is 2.58 x
Kg
<h3>
Relationship between Linear and angular speed</h3>
Linear speed is the product of angular speed and the maximum displacement of the particle. That is,
V = Wr
Where
Given that the earth orbits the sun at an average circular radius of about 149.60 million kilometers every 365.26 Earth days.
a) To determine the Earth’s average orbital speed, we will make use of the below formula to calculate angular speed
W = 2
/T
W = (2 x 3.143) / (365.26 x 24)
W = 6.283 / 876624
W = 7.2 x
Rad/hr
The Earth’s average orbital speed V = Wr
V = 7.2 x
x 149.6 x 
V = 107225.5 kilometers per hours.
b) Based on the information given in this question, to calculate the approximate mass of the Sun, we will use Kepler's 3rd law
M = (4
) / G
M = (4 x 9.8696 x 3.35 x
) / (6.67 x
x 7.68 x
<em>)</em>
<em>M = 1.32 x </em>
/ 51.226
M = 2.58 x
Kg
Therefore, the Earth’s average orbital speed expressed in kilometers per hours is 107225.5 Km/hr and the mass of the sun is 2.58 x
Kg
Learn more about Orbital Speed here: brainly.com/question/22247460
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