Answer:
The speed is constant.
Speed is a scalar quantity (magnitude only).
Velocity is a vector quantity (magnitude and direction).
For an object in Uniform Circular Motion the change in velocity is always
directed towards the center of the circle, and this change of velocity
gives rise to the acceleration which is directed towards the center of
rotation. This is called the centripetal acceleration, and it is the centripetal
force (for instance the attraction of the moon towards the earth) which
produces the centripetal acceleration.
Answer:
Part a)

Part b)

Part c)

Explanation:
Part a)
As we know that there is no external torque on the system of two twins
so here we will use



Part b)
Since angular momentum is conserved here as there is no external torque
so we will have



Part c)
Work done by both of them = change in kinetic energy
so we have




Answer: Part of Europe, part of Africa, part of Antarctic and the entire America.
Explanation: Western hemisphere or west hemisphere encompasses all regions located west of the longitude 0 °, or meridian of Greenwich.
The formal regions located in the western hemisphere is Europe, Africa, Antarctic and America.
1 is b because a runs 20 and b rus 102 is c