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J K L The graph in the figure shows the position of an object as a function of time. The letters H-L represent particular moments of time. At which moments shown (H, I, etc.) is the speed of the object the greatest? + Position H I K Time

1. Two pendula of slightly different length oscillate next to each other. The short one oscillates with frequency 0.52 Hz and the longer one with frequency 0.50 Hz. If they start of in phase determine their phase difference after 75 s.

A mass is connect to a vertical revolving axle by two strings of length L, each making an angle of 45 degrees with the axle, as shown. Both the axle and mass are revolving with angular velocity w, Gravity is directed downward. The tension in the upper string is T_upper and the tension in the lower string is T_lower.Draw a clear free body diagram for mass m. Please include real forces only.Find the tensions in the upper and lower strings, T_upper and T_lower

2. A stone is dropped into a pool of water causing ripple to spread out. After 10 s the circumference of the ripple is 20 m. Calculate the velocity of the wave.

10. Imagine you have a system in which you have 54 grams of ice. You can melt this ice and then vaporize it all at 0 C. The melting and vaporization are done reversibly into a balloon held at a pressure of 0.250 bar. Here are some facts about water you may wish to know. The density of liquid water at 0 C is 1 g/cm³. The density of ice at 0 C is 0.917 g/cm³. The enthalpy of vaporization of liquid water is 2.496 kJ/gram and the enthalpy of fusion of solid water is 333.55 J/gram. A. How much energy does the ice absorb as heat when it melts? B. How much work is involved in melting the ice? C. What is the total change in energy for melting the ice? D. What is the enthalpy change for melting the ice? E. What is the entropy change for melting the ice? F. What is the change in Helmholtz energy for melting the ice? G. What is the change in Gibbs energy for melting the ice?

In the figure Q = 5.7 nC and all other quantities are accurate to 2 significant figures. What is the magnitude of the force on the charge Q? (k = 1/4πε 0 = 8.99 × 109 N · m2/C2)

Now add a fourth charged particle, particle 3, with positive charge q3, fixed in the yz-plane at (0,d2,d2). What is the net force F→ on particle 0 due solely to this charge? Express your answer (a vector) using k, q0, q3, d2, i^, j^, and k^. Include only the force caused by particle 3.

For a tornadoes and hurricanes, which of the following is most critical? an alert a watch     a warning a prediction