Answer:
takes 365 days and it bring us seasons such as, spring,winter and fall.
To find the ratio of planetary speeds Va/Vb we need the orbital velocity formula:
V=√({G*M}/R), where G is the gravitational constant, M is the mass of the distant star and R is the distance of the planet from the star it is orbiting.
So Va/Vb=[√( {G*M}/Ra) ] / [√( {G*M}/Rb) ], in our case Ra = 7.8*Rb
Va/Vb=[ √( {G*M}/{7.8*Rb} ) ] / [√( {G*M}/Rb )], we put everything under one square root by the rule: (√a) / (√b) = √(a/b)
Va/Vb=√ [ { (G*M)/(7.8*Rb) } / { (G*M)/(Rb) } ], when we cancel out G, M and Rb we get:
Va/Vb=√(1/7.8)/(1/1)=√(1/7.8)=0.358 so the ratio of Va/Vb = 0.358.
Answer:
a) 
b) 
c) 
Explanation:
Given masses:


Velocity of mass 1, 
Velocity of mass 2, 
a)
Initial momentum:



b)
magnitude of initial momentum:


From the conservation of momentum:



is the magnitude of final velocity.
Direction of final velocity will be in the direction of momentum:




c)
Vertical component of final velocity:


Gravitational energy and motion energy