A uniform drawbridge 9m long is attached to the roadway by a frictionless hinge at one end and can be
raised by a cable at the other end. The bridge is at rest suspended 30 degrees above the horizontal when
the cable breaks. (a) Find the angular acceleration of the drawbridge just as the cable breaks. (b) What is
the angular speed of the drawbridge when it becomes horizontal?

Asmall metal bar, whose initial temperature was 10° c, is dropped into a large container of boiling water. how long will it take the bar to reach 70° c if it is known that its temperature increases 2° during the first second? (the boiling temperature for water is 100° c. round your answer to one decimal place.) sec how long will it take the bar to reach 98° c? (round your answer to one decimal place.)

When you push downward on a book at rest on a table, you feel an upward force. does this force depend on friction? defend your answer.

4. now look at the green lines you created by connecting the three boiling point data points and the three melting point data points. for each of these lines, describe any trends you see. 5. locate the elements on your periodic table that you circled in green on your graph. what term or description would you use to identify these elements with respect to the periodic table? 7. using the room temperature line (orange line) and your periodic table, make lists that identify the state of matter (gas, liquid, or solid) in which each element you plotted exists at room temperature. explain your answers.