Astronomers, who are interested in finding life elsewhere in the Universe, are searching for planets orbiting other stars. A planet will be too small to see, but still can cause a star to appear to wobble as the planet orbits it. One such wobbling star is 47 Ursae Majoris, which has a mass of 2.2 × 1030 kg. The period of its wobble is 9.2 × 107 s. From the wobble, the astronomers deduced that there is a planet of mass 4.5 × 1027 kg orbiting 47 Ursae Majoris with a force on the star due to this planet is about 7 × 1024 N. A) calculate the orbital distance of the planet from Ursae Majoris.

B) the star is orbiting about the centre of mass of the star/planet system. Calculate the speed of the star in its orbit.

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a solenoid is created by wrapping a l = 90 m long wire around a hollow tube of diameter d = 4.5 cm.   the wire diameter is d = 0.9 mm.   the solenoid wire is then connected to a power supply so that a current of i = 9 a flows through the wire.

randomized variablesl = 90 m

d = 4.5 cm

d = 0.9 mm

i = 9 a                                          

write an expression for the number of turns, n, in the solenoid. you do not need to take into account the diameter of the wire in this calculation.

calculate the number of turns, n, in the solenoid.

write an expression for the length of the solenoid (l2) in terms of the diameter of the hollow tube d.

calculate the length of the solenoid (l2)   in meters.

calculate the magnitude of the magnetic field at the center of the solenoid in teslas.

explanation:

6 cos 34, 6 sin 34 trig