-- reduce the length of a wire to 1/2 . . . cut the resistance in half
-- reduce the diameter to 1/4 . . . reduce the cross-section area by (1/4²) . . . increase the resistance by 16x .
-- R2 = (R1) · (1/2) · (16) = 8 · R1
<em>-- R2 / R1 = 8</em>
Answer:
Explanation:
a) According to ohm's law
V = IR
V is the supply voltage
R is the resistance
I is the current
Given Resistance = 200ohms
Voltage = 20V
I = V/R
I = 20/200
I = 0.1Amperes
b) Using the ohm's law formula
V= IR
Where voltage = 12volts
Current I = 3A
Resistance R = V/I
R = 12/3
R = 4ohms
c) Power generated by the battery is expressed as P = IV
I = P/V
Given Power = 2Watts
V = 1.5volts
I = 2/1.5
I = 1.33A
d) similarly, power = current I × voltage V
V = P/I
Given P = 90watts
I = 4.5A
V = 90/4.5
V = 20volts
e) Given power = 1.5kW = 1500watts
Voltage = 300volts
I = P/V
I = 1500/300
I = 5A
Answer:
0.186 N-m
Explanation:
mass of the grindstone, 
radius, 
Frequency, 
time, 
final angular velocity, 
Initial angular velocity,
Angular acceleration of the grind stone is:
Moment of inertia:
Torque exerted by the ax on the grind stone is:
To develop this problem it is necessary to apply the concepts performed to the absolute pressure based on the reference pressure (atmospheric) and the pressure that is generated due to the height of the column of the measured liquid.
In mathematical terms the previous concept can be expressed as
Where
Atmospheric Pressure
Density
g = Gravitational acceleration
h = Height
Our values are given as
g = 9.8m/s
Replacing we have then that
Therefore the absolute pressure in the test section is 99.9019kPa
Answer:
Our atmosphere has five different layers. They are:
1. Troposphere: This is the most important layer of the atmosphere with an average height of 13 km from the earth. It is in this layer that we find the air that we breathe. Almost all the weather phenomena such as rainfall, fog and hailstorm occur here.
2. Stratosphere: This layer extends up to a height of 50 km. It presents the most ideal condition for flying airplanes. It contains a layer of ozone gas which protects us from the harmful effect of the sun rays.
3. Mesosphere: This layer extends up to a height of 80 km. Meteorites bum up in this layer on entering from the space.
4. Thermosphere: In this layer, the temperature rises very rapidly with increasing height. The ionosphere is a part of this layer. It extends between 80-400 km. This layer helps in radio transmission. Radio waves transmitted from the earth the reflected back to the earth by this layer.
5. Exosphere: It is the uppermost layer where there is very thin air. Light gases such as helium and hydrogen float into space from here.
