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Each week, we highlight one of our many demonstrations by asking a physics question relevant to the topic designed to be illustrated. This not only challenges audiences to carefully examine their previously held views on physics, but also provides suggestions for teachers looking to use these demonstrations in their own classrooms.

Be sure to check back each week for the solutions to the previous weeks' questions and for newest question of the week.

  • Question of the Week Archive
  • Question of the Week 1/26 - 1/30
  • Question of the Week 1/19-1/23 with Answer
  • Question of the Week 1/12-1/16 with Answer
  • Question of the Week 1/5-1/9 with Answer

Missed one of our older Question of the Weeks? Click here to access our archive.

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In the photograph you see a graduated cylinder containing blue water, and a spherical flask.

 

If you pour the water from the graduated cylinder into the flask, which of the following statements will be true?

  • (a) The water will not fill up the sphere.
  • (b) The final water level will be somewhere in the cylindrical neck of the flask.
  • (c) The water in the cylinder will not fit into the flask.

 

After January 30th, 2015, click Read More for the answer.

 

 

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A pendulum, shown in the photograph below, is lifted to the 30 cm level toward the left of the picture and released.  When it falls down to its minimum level, just below the suspension point, it encounters a peg at the 35 cm level.  What will then happen?  In particular, how high will the pendulum rise as it moves to the right?  When the string hits the peg, how will that encounter effect the angular momentum?  Will it be sufficiently increased such that it will rotate over the pin?

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The pendulum bob will:

  • (a) rise to a height less than 30.
  • (b) rise to a height of 30.
  • (c) rise to a height of greater than 30.
  • (d) loop around the lower peg.

To see the answer, click Read More on 1/23/15

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Shown in the photograh below is a picture with the left side bright  magenta and the right side pure bright green, with a black spot in the  center of the slide.

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Suppose that you stare at the black spot for about 20-30 seconds, then  quickly replace this slide with one that has the same green field on the  right side but the magenta field at the left is replaced by a white  field. 

Which of the following statements will be true?

  • (a) Both sides will be the same color.
  • (b) Both sides will be very close to white.
  • (c) Both sides will be very close to black.
  • (d) The left side will be black and the right side will be green.
  • (e) The left side will be magenta and the right side will be black.
  • (f) The left side will be  bright green and the right side will be  pale green.
  • (g) The left side will be pale green and the right side will be  bright green.
  • (h) The left side will be green and the right side will be magenta.
  • (i) Other, to be explained by the viewer.

To see the answer, click Read More on 1/16/15

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A radio is tuned to Washington, DC, SportsTalk 980 when it is suddenly and for no apparent reason covered by the wire mesh seen in the photograph below.

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What happens to the sound of the radio after the wire mesh is in place?

After placing the wire mesh on the radio, the radio will:

  • (a) be louder.
  • (b) be softer.
  • (c) remain at about the same volume.

To see the answer, click Read More on 1/9/15

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