9. State which of the following situations are possible and give
an example for each of these:
(a) an object with a constant acceleration but with zero velocity
(b) an object moving with an acceleration but with uniform
speed.
(c) an object moving in a certain direction with an
acceleration in the perpendicular direction.
10. An artificial satellite is moving in a circular orbit of radius
42250 km. Calculate its speed if it takes 24 hours to revolve
around the earth.
Answers
(a) The given statement is possible.
The word acceleration implies a change in the object's velocity. One example of this is vertical particle projection. When an object is thrown upwards, the maximum height velocity of the body is zero, but the constant acceleration due to gravity is still working.
(b) Because, the velocity keeps on changing due to continuous change in the direction of motion. Therefore, circular motion is an example of an object moving with an acceleration but with uniform speed.
(c) The given statement is possible.
The given statement is possible.The object can move in a certain path with a perpendicular acceleration, in the case of circular motion. When an object is moving along a circular motion its path is along the circle tangent but the centripetal acceleration is towards the circle radius.