In a Visual Binary System with Circular Orbits, If in 20

question 61

Multiple Choice

In a visual binary system with circular orbits, if in 20 years the two stars' position angleshave shifted by 30 degrees, the pair's period must be:

• A)60 years.
• B)90 years.
• C)120 years.
• D)240 years.
• E)360 years.

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Definitions:

Shunt Rheostat

A variable resistor connected in parallel with a circuit element to adjust the flow of current through it, allowing for the control of electrical device performance.

Series Rheostat

An adjustable resistor used in series with a circuit to control the current flow by varying its resistance.

Field Exciter

A device or circuit that provides the necessary DC current to the magnetic field winding of a generator or motor to initiate or enhance its operation.

Differential Setting

In protective relays, refers to the adjustment that determines the difference in current or voltage at which the device will operate to protect electrical equipment.