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Questions in physics

[Done] P waves move through the crust at a speed of about 6.5 km/s. How far will the P wave move in 5 seconds?

[Done] A radio station has a frequency of 90.9 megahertz ([tex]9.09 \times 10^7[/tex] Hz). What is the wavelength of the radio waves the station emits from its radio tower?

[Done] In order to determine speed, you must know: A. time B. distance C. Both (A) and (B) D. None of the above

[Done] What object circles around a planet?

[Done] A 2 kg mass is held 4 m above the ground. What is the approximate potential energy due to gravity of the mass with respect to the ground?

[Done] What is the average speed of a cheetah that runs 70 meters in 2.5 seconds?

[Done] Oliver weighs 600 N. He climbs a flight of stairs that is 3.0 meters tall in 4.0 seconds. a. How much work did he do? b. What was Oliver’s power in watts?

[Done] A butterfly has a wingspan of 66 mm and a height of 6 cm. Which is greater, its wingspan or its height?

[Done] The speed of light is about \(3.00 \times 10^5\) km/s. It takes approximately 1.28 seconds for light reflected from the moon to reach Earth. What is the average distance from Earth to the moon?

[Done] Dogs can hear much higher frequencies than humans. Therefore, dog whistles, which are inaudible to the human ear, can be heard by dogs. If a dog whistle has a frequency of 30,000 Hz, what is the wavelength of the sound emitted?