A child pulls a wagon at a constant velocity of 4.0 m/s for 4.0 minutes along a level sidewalk. The child does this applying a 22 N force to the wagon handle, which is inclined at 35 ° to the sidewalk as shown below. How much work does the child do on the wagon ? 288 k J
8.7 kJ
17.3 kJ
2.3 kJ

Zirconium has an hcp crystal structure and a density of 6.51 g/cm3. (a) what is the volume of its unit cell in m3? (b) if the c/a ratio is 1.593, compute the values of c and a.

During a medieval siege of a castle, the attacking army uses a trebuchet to hurl heavy stones at the castle walls. if the trebuchet launches the stones with a velocity of at an angle of 50.0°, (a) how long does it take the stone to hit the ground? (b) what is the maximum distance that the trebuchet can be from the castle wall to be in range? (c) how high will the stones go? show all your work.

If you let go of the notebook after lifting it, will it move? how?