Answer:
Given that
D= 4 mm
K = 160 W/m-K
h=h = 220 W/m²-K
ηf = 0.65
We know that

For circular fin


m = 37.08


By solving above equation we get
L= 36.18 mm
The effectiveness for circular fin given as


ε = 23.52
Answer:
Current in the loop is 0.063 A
Explanation:
Number of turns in the coil N = 150
Radius of the circular loop r = 7.5 cm = 0.075 m
So area 
Magnetic field B = 1.5 T
Maximum torque is given 
We have to find current in the coil
Torque on circular coil in magnetic field is equal to


I = 0.063 A
-- The long line and short line close together at the left side
of the diagram represent a single-cell battery.
It's the only one in this diagram.
It's a device that stores chemical energy and delivers it on demand.
-- The zig-zag lines with circles around them represent light bulbs.
There are three of them in this diagram.
They are devices used to produce light by dissipating electrical energy.
-- The zig-zag lines without circles, at the top of the diagram,
represent resistors.
There are two of them in this diagram.
They are devices used to change or control electrical parameters
within a circuit by dissipating electrical energy.
-- The short straight line between two small circles at the bottom
of the diagram represents a switch.
There is only one switch in this circuit.
It's a device used to easily and quickly start or stop the flow of current
past a certain point in a circuit.
In this circuit ...
-- When the switch is closed (as drawn), the light bulb nearest the battery
glows brightest, the light bulb in the middle glows less bright, and the light
bulb on the right side glows dimmest of all.
-- When the switch is open, the light bulb nearest the battery glows, and
neither of the other two light bulbs glows at all.
Answer:
the number of turns in the primary coil is 13000
Explanation:
Given the data in the question;
V₁ = 13000 V
V₂ = 120 V
N₁ = ?
N₂ = 120 turns
the relation between the voltages and the number of turns in the primary and secondary coils can be expressed as;
V₁/V₂ = N₁/N₂
V₁N₂ = V₂N₁
N₁ = V₁N₂ / V₂
so we substitute
N₁ = (13000 V × 120 turns) / 120 V
N₁ = 1560000 V-turns / 120 V
N₁ = 13000 turns
Therefore, the number of turns in the primary coil is 13000
Explanation:
KE = 1/2*m*v^2
mass won't change
but velocity is
A: the force is pushing against the direction of the object, so velocity is decreasing, so KE is decreasing
B: the F net line is pretty much straight up, which means there is no net force pushing to the left, but velocity is still increasing
Why? Because if you use the pythagorean theorem, the hypotenuse is always longer than the legs.
Note: velocity only ever stays the same if there is no net force (or 0 acceleration), so all four of these are either decreasing or increasing
C: there is a net force to the right, so velocity is increasing
D: There is a net force to the right but velocity is to the left, so velocity is decreasing
Hope I got these right