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:
An element is a pure substance that contains only one type of atom. TRUE. 2. ... FALSE, they are all carbon atoms. 7. The smallest unit of matter is an atom. TRUE. 8. When an ... TRUE. 10. Most of the mass of an atom is found in the electron layers. FALSE. 11. The nucleus of an atom contains protons and neutrons. TRUE ...
Explanation:
Actually, when the refrigeration liquid is vaporized, the cooling effect is produced
Answer:
1.53 seconds
Explanation:
Applying,
T = 2usin∅/g................ Equation 1
Where, T = time of flight, u = initial velocity, ∅ = angle of projectile to the horizontal, g = acceleration due to gravity
From the question,
Given: u = 15 m/s, ∅ = 30°
Constant: g = 9.8 m/s²
Substitute these values in equation 1
T = 2(15)(sin30°)/9.8
T = 15/9.8
T = 1.53 seconds
Hence the time rate of flight is 1.53 seconds
I believe it is False, only because the plane is Frictionless. Hope this helps, good luck.
