The answer is number 2) Increase the resistance of the concrete to freeze-thaw damage.
Answer:
Tech B
Explanation:
Horsepower (hp) refers to a unit of measurement of power in respect of the output of engines or motors.
Horsepower is the common unit of power. It indicates the rate at which work is done.
The formula
, where rpm is the engine speed, T is the torque, and 5,252 is radians per second.
So,
Tech B is correct
Answer and Explanation:
Commutator are used in DC machine commutator is mainly used for the reversing the direction of the current .It is connected to the armature of the DC generator or motor
ADVANTAGE OF COMMUTATOR The main advantage of the commutator in DC motor is to keep keep the direction of the toque always in the same direction by changing the current direction
DISADVANTAGE OF COMMUTATOR : The main disadvantage is due to the friction between the commutator and brushes there is a friction loss.