Answer:
(1) The orbits are ellipses, with focal points ƒ1 and ƒ2 for the first planet and ƒ1 and ƒ3 for the second planet. The Sun is placed in focal point ƒ1.
(2) The two shaded sectors A1 and A2 have the same surface area and the time for planet 1 to cover segment A1 is equal to the time to cover segment A2.
(3) The total orbit times for planet 1 and planet 2 have a ratio a13/2 : a23/2
Its very simple if a body is moving in circle the magnitude of its velocity remain constant but its direction changes because velocity is directed towards tangent and at every point in a cirlce its direction will be different (along tangent) so velocity is not uniform .As acceleration is the rate change of velocity so it will be non zero because velocity is changing due to its direction.
<h3>
Answer: 130 meters</h3>
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Explanation:
vi = 5 and vf = 8 are the initial and final velocities respectively. The change in time is t = 20 seconds.
So,
x = 0.5*(vi + vf)*t
x = 0.5*(5+8)*20
x = 130 meters
represents the distance traveled. The first equation shown above is one of the four kinematics equations.