Answer:
A _commutator_ is used in a motor to switch the direction of the magnetic field created by the current.
The rotating part of a motor that holds the electromagnets is called the __armature___.
Electric current passes through the _brushes_ and into the electromagnets in an electric motor.
A motor turns _electrical_ energy into _mechanical_ energy.
Explanation:
A commutator, which is a split ring rotary switching device, reverses the direction of the current between the external circuit and the rotor. Reversing the current reverses the magnetic field.
The armature comprises the rotating part of the motor and the electromagnets
A brush is the electrical contact for conducting current through the moving and stationary parts of an electric motor
An electric motor turns electrical energy into mechanical energy.
Answer:
Speed will be 30810 rpm
Explanation:
We have given diameter of the tire d = 24 inch
So radius 
We have given linear velocity v = 35 mph
We know that linear velocity is given by 


As we know that 1 mile = 63360 inch and 1 hour = 60 min
Answer:
The length of the Mercury column of thermometer at ice point is 20mm and 220mm at steam point . when the same Thermometer is placed in contact with another body ,it reads 5°c.what will the length of the Mercury column at the temperature?
Answer:
INCREASES, BECAUSE ITS ANGULAR MOMENTUM IS CONSERVED.
Explanation: Interstellar cloud of Hydrogen is an accumulation of Hydrogen gas in the cloud.
As the Interstellar cloud of Hydrogen shrinks (reduces) in size,the rate of rotation of the shrinked Interstellar cloud Increases because its angular momentum is conserved. GASEOUS MOLECULES MAKE UP ABOUT 99% OF THE INTERSTELLAR CLOUD WITH HYDROGEN HAVING ABOUT 90% OF THE VOLUME OF GASES IN THE INTERSTELLAR CLOUD.
Tycho Brahe ( 1546 - 1601 ) was a Danish astronomer known for his accurate astronomical and planetary observations. Tycho tried to produce a model with the best of both Ptolemy ( earth-centered solar system ) and Copernicus ( sun-centered solar system ).
Answer: B ) observation.