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The period of Venus is 225 days. What is it's semi major axis?

In each hand you hold a 0.16 kg peach. What is the gravitational force exerted by one peach on the other when their separation is (a) 0.25 m (b) 0.50 m?

A 7.3 kg bowling ball is placed on a shelf 1.7 m above the floor. What is its gravitational potential energy?

An object has a speed of 3.5 m/s and a kinetic energy of 14 J at t=0. At t=5 the object has a speed of 4.7 m/s. (a) what is the mass of the object? (b) what is the kinetic energy of the object at t=5?

7. As you lift an 88 N box straight upward 3 m, you produce a power of 72 W. How long did it take to lift the box?

20. How much thermal energy must be removed from a 0.21 kg chunk of ice to lower its temperature by 7.5 C?

21. You add 0.0550 kg of ice at -10.2 C to a 3.99 kg bowl of water at 20.5 C. What is the final temperature of the system?

22. How much energy is required to take 4.0g of -13 C ice and turn it to 115 C steam?

24. A runner does 8.2 x 105 J of work and gives off 3.3 x 105 J of heat. What is the change in internal energy?

25. An engine receives 770 J of heat from a hot reservoir and does 160 J or work. What is (a) the efficiency of the engine and (b) the heat given off to the cold reservoir?

26. A fluid expands by 0.42 m3 at a pressure of 121 kPa. How much work is done by the fluid?

27. A gas expands at a constant pressure of 190 kPa and does 82J of work. What is the change in volume?

30. How fast would a motorist have to be traveling for a yellow (590 nm) traffic light to appear green (550nm) because of Doppler shift? Should the motorist be traveling toward or away from the traffic light to see this shift?

31. Two starships, the Enterprise and the Constitution are approaching each other head on from a great distance. The separation between them is decreasing at a rate of 722.5 km/s. The Enterprise sends a laser signal toward the Constitution. If the Constitution observes a wavelength of 670.3 nm, what wavelength was emitted by the Enterprise?

32. A cell phone transmits at a frequency of 1.25 x 108 Hz. What is the wavelength of the electromagnetic waves emitted by this phone?

34. A TV screen is half blue and half white. The screen has 3,000,000 pixels. How many red dots are lit? How many green dots are lit? How many blue dots are lit?

41. Vertically polarized light with an intensity of 0.23 W/m2 passes through a polarizer whose transmission axis is at an angle 42.0 with the vertical. What is the final intensity?

42. Vertically polarized light passes through a polarizer whose transmission axis is at an angle to the vertical. If the initial intensity of the light is 0.54 W/m2 and the final intensity is 0.22 W/m2, what angle does the transmission axis of the polarizer make with the vertical?