A dog whistle has an average frequency of 30 kHz. At room temperature (where the speed of sound is ~340 m/s), what is the wavelength of the sound created by the whistle (in meters)?

You hang a book bag on a spring scale and place the bag on a platform scale so that the platform scale reads 23.7n and the spring scale reads 13.8n. what is the magnitude of the force that earth exerts on the bag?

How does the electric potential energy between two charged particles change if one particle is reduced by a factor of 3? a. increased by a factor of 3 b. it is decreased by a factor of 9 c. it is reduced by a factor of 3 d. it is increased by a factor of 9

What equation is used to calculate the weight of an object on a plant ?