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An exo-planet orbits its local star, of mass 2.00x10^30kg, in a steady circular orbit of radius 8.00x10^8km. Calculate the orbital period of the star, in years.

Key idea is equating gravitational force between planet and star (right hand side) with the centripetal force necessary to maintain the orbit (left hand side):(mv2)/r = (GMm)/r2

Answered by • Physics tutor
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Discuss how the graph of orbital velocities in rotational galaxies against distance from the galactic centre implies the existence of dark matter.

Within the central swell of the galaxy, we can see that the orbital velocity increases almost linearly with distance, which corresponds with the formula for orbital velocity (namely that v=sqrt(GM/r)), as...

Answered by Jack T. • Physics tutor
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What is the difference between Speed, Velocity and Acceleration?

Speed and Velocity are both measures of distance travelled in a given time and are therefore calculated using Speed=Distance/Time.Speed is a scalar quantity which means that it is quantified by a magnitud...

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pressure = 2.3 × 10^5 Pa temperature= 200K. At a constant volume, when the temperature increases to 300K what is the pressure in Pa?

Divide pressure by temperature to get the constant = 1150. Making sure all values are in the correct units.Then multiply by 300K to get the increased pressure. 3.45 x 10^5 Pa

Answered by Rebecca P. • Physics tutor
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What is the Rutherford alpha scattering experiment and what does it tell us?

The Rutherford experiment allowed us to experimentally disprove older models of the atom, forming the basis of the evidence for the nuclear model of the atom. The atom at the time was bel...

Answered by Aneesh J. • Physics tutor
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