When only acts on an object's mechanical energy is conserved. A.) Gravity
B.) Friction
C.) Air resistance
D.) Momentum

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A2 µc charge q1 and a 2 µc charge q2 are 0.3 m from the x-axis. a 4 µc charge q3 is 0.4 m from the y-axis. the distances d13 and d23 are 0.5 m. find the magnitude and direction of the resulting vector r. round your answer to the nearest tenth.

Act has a 1200: 5 or 240: 1 turns ratio. it is short circuited. what is the maximum current at 1200a primary if we put a 100ohm resistor across the secondary end of the ct. use it as current source circuit.

The two stars in a certain binary star system move in circular orbits. the first star, alpha, has an orbital speed of 36 km/s. the second star, beta, has an orbital speed of 12 km/s. the orbital period is 137 d. a) what is the mass of the star alpha? b) what is the mass of the star beta?