This week's question is a two-part follow-up to Questions of the Week #119 and #123.
A mass M on a level air track is connected by a string passing over a pulley to a much smaller mass m<<M, as seen in the photograph at the left below.
Releasing M allows m to accelerate it along the air track. The timer measures the time taken for a flag on the top of the air track glider to travel from photocell gate "A" to gate "B," which turns out to be exactly 2.00 seconds. See a video of the action by clicking your mouse on the photograph above.
Suppose that the same experiment is performed with both mass m increased to 2m and mass M increased to 2M, as seen in the photograph at the center above. How long will the glider take to travel from photocell gate "A" to gate "B"?
The time taken for mass 2m to accelerate mass 2M a distance of D from A to B will be:
Now suppose that the same experiment is performed with mass M increased to 2M and distance D decreased to D/2, as seen in the photograph at the right above. How long will the glider take to travel from photocell gate "A" to gate "B"?
The time taken for mass m to accelerate mass 2M a distance of D/2 from A to B will be:
Click here for Answer #135 after January 20, 2003.
