(A)if you decide to ride your motorbike in a counter clockwise direction as your speed increases does your rotational speed increases decreases or remain the same   ?     (B)how fast would you have to be going and in what direction to experince weightlessness?

Expert Answers

An illustration of the letter 'A' in a speech bubbles


In a circular motion the relationship between the rotational speed (or in other words angular speed) `omega` and linear speed `v` is given by the relation

`v= omega*R`  , or equivalent `omega= v/R`

where R is the radius of the circular trajectory.

So the answer is as long as the radius od the trajectory does not change in time the rotational speed increases with the linear speed in the circular motion.


To experience zero weight the condition is that the centrifugal force equals the weight itself. This happens at the top of a circular trajectory if the plane of the trajectory is perpendicular to the earth (see the figure below). Thus

`G =F_(cf)`

`m*g =m*a_(cf)`

`g = v^2/R`

`v= sqrt(g*R)` , where `R` is the radius of the trajectory.

You need to go upwards (see the figure) to experience zero weight.

This image has been Flagged as inappropriate Click to unflag
Image (1 of 1)
Approved by eNotes Editorial Team

We’ll help your grades soar

Start your 48-hour free trial and unlock all the summaries, Q&A, and analyses you need to get better grades now.

  • 30,000+ book summaries
  • 20% study tools discount
  • Ad-free content
  • PDF downloads
  • 300,000+ answers
  • 5-star customer support
Start your 48-Hour Free Trial