Describe two ways to change the frictional force between two solid surfaces.

During takeoff, the sound intensity level of a jet engine is 170db at a distance of 34 m. what's the sound intensity level at a distance of 1.0 km?

Question part points submissions used suppose that 2 j of work is needed to stretch a spring from its natural length of 26 cm to a length of 36 cm. (a) how much work is needed to stretch the spring from 28 cm to 32 cm? (round your answer to two decimal places.)

Select light for the type of wave, adjust the wavelength so that the light is red, and increase the amplitude of the light to the max. then, select the start button at the source location to begin producing the waves. light is a form of electromagnetic wave, containing oscillating electric and magnetic fields. the wave amplitude detector mentioned above shows how the electric field oscillates in time at the location of the probe. the amplitude of the wave at the location of the probe is equal to the maximum electric field measured. how does the amplitude of the wave depend on the distance from the source?