Answer
Correct Answer is B(to change direct current into alternating current)
Explanation
commutation
The main aim of commutation is to maintain the torque acting on armature of DC motros in the same direction.
commutator a switch which is used to convert the direction of flow of electric current it is connected to the armature of DC motor.
In DC motors, voltage across the armature is alternating in nature. The direction of this current is reverses by Commutator when armature of DC motors passes through magnetic neutral axis to maintain the unidirectional. Hence, commutator is used to change direct current into alternating current.
Answer:
it is hit by an external force
Explanation:
Earth's surface warms up in the sunlight. At night, Earth's surface cools, releasing the heat back into the air. But some of the heat istrapped<span> by the greenhouse </span>gases<span> in the </span>atmosphere<span>. ... Greenhouse </span>effect<span> of Earth's </span>atmosphere<span> keeps some of the Sun's energy from escaping back into space at night.</span>
The torque required to loosen the bolt when perpendicular was:
t = 60N x 0.3 = 18 Nm
To have the same torque applied at 30 degrees:
18 Nm = Force x 0.3cos(30 degrees)
Simplify:
18 Nm = Force x 0.2598
Force = 18Nm / 0.2598
Force = 69.28 N
Round the answer as needed.