Problem 11: Suppose you have a device that extracts energy from ocean waves in direct proportion to their intensity. If the device produces 9.5 kW of power on a day when the waves are 1.3 m high, how many kilowatts will it produce when they are 0.625 m high? Numeric : A numeric value is expected and not an expression. P2 =

21.A block is suspended from the ceiling by a long, thin strip of tungsten metal. The strip behaves as a spring. To produce a 0.25 m horizontal deflection of the block, a force of 6.5 N is required. Calculate the spring constant(k) for the tungsten strip. 6.3 N 0.25 m A) 0.038 N/m B) 1.2 N/m C) 1.6 N/m D) 13 N/m E) 26 N/m 22. Which one of the following statements conceming streamline flow is true? A) At any given point in the fluid, the velocity is constant in time. B) Streamline flow occurs when there are sharp obstacles in the path of a fast- moving fluid. C) Streamline flow is described by Pascal's principle. D) Streamline flow is described by Archimedes' principle. E) The velocity vectors are the same for all particles in the fluid.

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9. Because of the inverse relation between Xc and f, the graph of Xc versus C is A. impossible to plot B. nonlinear C. linear D. exponential

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A block of mass 0.688 kilograms resting on a smooth horizontal surface is attached to a spring with a spring constant of 33.4 newtons per meter. The block is pulled horizontally 14.1 centimeters from its equilibrium position and released. a. What is the total mechanical energy of the system? Include units in your answer. b. What is the speed of the block when it is 9.0 centimeters from its equilibrium position? Include units in your answer. c. One end of the spring is then attached to a support so it hangs vertically, and the block is suspended from it and lowered into a resting position. How far does the block stretch the spring? Include units in your answer. d. As shown below, the block is then lifted 14.1 centimeters (labeled d in the figure) and released. What is the speed of the block when it is 9.0 centimeters from its equilibrium position (labeled y in the figure)? Include units in your answer. More information. Hint: Since the vertical position of the block is changing,…

Question 6 When a student stretches a spring, what is the flow of energy? a. Energy goes into the spring and into the student. X b. There is no change in the energy of the spring, only for the student. c. There is no change in the energy of the student, but there is a change for the spring. d. Envery leaves the spring and goes to the student. e. Energy goes into the spring from the student.

A block of mass 0.688 kilograms resting on a smooth horizontal surface is attached to a spring with a spring constant of 33.4 newtons per meter. The block is pulled horizontally 14.1 centimeters from its equilibrium position and released. a. What is the total mechanical energy of the system? Include units in your answer. b. What is the speed of the block when it is 9.0 centimeters from its equilibrium position? Include units in your answer. c. One end of the spring is then attached to a support so it hangs vertically, and the block is suspended from it and lowered into a resting position. How far does the block stretch the spring? Include units in your answer. d. As shown below, the block is then lifted 14.1 centimeters (labeled d in the figure) and released. What is the speed of the block when it is 9.0 centimeters from its equilibrium position (labeled y in the figure)? Include units in your answer. More information. Hint: Since the vertical position of the block is changing,…

Suppose a force of 40 N is required to stretch and hold a spring 0.2 m from its equilibrium position. a. Assuming the spring obeys Hooke's law, find the spring constant k. b. How much work is required to compress the spring 0.4 m from its equilibrium position? c. How much work is required to stretch the spring 0.3 m from its equilibrium position? d. How much additional work is required to stretch the spring 0.2 m if it has already been stretched 0.2 m from its equilibrium?

1. Which order of magnitude does the SI prefix “mega-“ (M) represent? A. 103 B. 106 C. 109 D. 1012 2. 2.34 kW is equal to A. 2 340 W. B. 23 400 W. C. 234 000 W. D. 2 340 000 W. 3. How many seconds (s) are there in 1 hour 20 minutes? A. 80 s B. 380 s C. 4800 s D. 87 600 s 4. It takes a kettle 5 minutes to transfer 540 kJ of energy to boil some water. What is the power of the kettle? A. 1080 W B. 1800 W C. 9000 W D. 108 000 W 5. A heater of power 1200 W is switched on for an hour and a half. How much heat is given out from the heater? A. 2.16 kJ B. 6.48 kJ C. 2.16 MJ D. 6.48 MJ 6. An immersion heater has a power of 1500 W. How long does it take to supply 3 000 000 J of heat? A. 2 minutes B. 5 minutes C. 20 minutes D. 33 minutes 7. An immersion heater is connected to power supply via a joulemeter. The figure below shows the variation of the reading of the joulemeter with time. Estimate the power of the immersion heater. A. 582 W B. 723…