If the radius of an object is doubled, the distance it moves in one revolution also doubles. This can be understood by considering the circumference of a circle, which is given by the formula C = 2πr, where C is the circumference and r is the radius. When the radius is doubled, the new circumference becomes C' = 2π(2r) = 4πr. As you can see, the new circumference is four times the original circumference.
Therefore, if the object completes one revolution, it will now cover a distance that is four times the distance it covered before. This means that the object moves a greater distance with the larger radius.
The effect on the speed of the object depends on the time taken to complete one revolution. If the time remains constant, the speed of the object will remain the same, regardless of the change in radius. Speed is defined as the distance traveled divided by the time taken. Since the distance traveled has doubled, but the time remains the same, the speed will stay constant.
However, if the time taken to complete one revolution changes, then the speed of the object will be affected. If the time is halved (i.e., the object completes one revolution in half the time it took before), the speed will double. Conversely, if the time is doubled, the speed will be halved.
In summary, doubling the radius of an object doubles the distance it moves in one revolution, while the speed remains constant if the time taken to complete one revolution remains the same.