Answer:
A.................. I think the answer
You can identify a substance, by testing the melting and boiling point and find a known substance that has the same melting and boiling points as the one tested
Tan2(∅) ≡ 2tan(∅) / (1 - tan²∅)
Thus,
2tan(∅) / (1 - tan²(∅)) + tan(∅) = 0
2tan(∅) / (1 - tan²(∅)) = -tan(∅)
1 - tan²(∅) = -2
tan²(∅) = 3
∅ = tan⁻¹(√3)
∅ = 4nπ/3
Answer:
This question doesnt make much sense but ill try to answer it.
A brushed DC electric motor is an internally commutated electric motor designed to be run from a direct current power source. Brushed motors were the first commercially important application of electricity. If the shaft of a DC motor is turned by an external force, the motor will act as a generator. DC Motor rotation does have to do with the voltage polarity and the direction of the current flow.
