Answer:
Commutator is a ring which reverse the direction of current in AC circuit so that the coil connected to it will continuous to move in the same direction.
Explanation:
In motors there exist a coil which is rotated due to torque of magnetic field when current flow through it. Since AC current is used to run the motor so we know that AC current changes its direction after half cycle.
So here commutator plays an important role to reverse the direction of current after every half cycle so that the current goes in same direction always into the coil.
This will produce a constant direction torque on the coil so that it will rotate in same sense always.
So commutator role is to provide same direction current to the coil by reversing its direction after every half cycle
Answer:
Required energy Q = 231 J
Explanation:
Given:
Specific heat of copper C = 0.385 J/g°C
Mass m = 20 g
ΔT = (50 - 20)°C = 30 °C
Find:
Required energy
Computation:
Q = mCΔT
Q = 20(0.385)(30)
Required energy Q = 231 J
Answer:
Explanation:
When 2 gms of steam condenses to water at 100 degree latent heat of vaporization is releases which is calculated as follows
Heat released = mass x latent heat of vaporization
= 2 x 2260 = 4520 J
When 2 gms of water at 100 degree is cooled to ice water at zero degree heat is releases which is calculated as follows
Heat released = mass x specific heat x( 100-0)
= 2 x 4.2 x 100 = 840 J
When 2 gms of water at zero degree condenses to ice at zero degree latent heat of fusion is releases which is calculated as follows
Heat released = mass x latent heat of fusion
= 2 x 334 = 668 J
When 2 grams of steam at 100 degrees Celsius turns to ice at 0 degrees Celsius heat released will be sum of all the heat released as mentioned above ie
4520 + 840 +668 = 6028 J
Answer:
Infrared
Explanation:
This is the electromagnetic spectrum just above the visible light spectrum with higher energy (and higher frequency). This electromagnetic radiation is responsible for feeling the heat when you place your hand close to the side of a fire. It is also harnessed in night vision where bodies that emit some form of heat are visible due to their emission of IR.
Answer:
why do people hate on people and hate country people. are you country
because they only think about. themselves and they also think that they are always right .
it's my point of view
hope it is helpful to you
