A boy pulls a 50 kg crate across a level floor with a force of 200 N. If the force acts at an angle of 30 degrees up from the horizontal, and the coefficient of kinetic friction is 0.30, determine A) the normal force exerted on the crate by the floor
B) the horizontal force exerted on the crate by the floor
C) the acceleration of the crate

If an athlete runs once around a track, back to the starting line, her average velocity is zero. true or false?

Although longitudinal waves can travel through all media types what is the disadvantage of this type of wave transmission? a) he efficiency of he wave transmission is greatly diminished as the media becomes less dense b) the oscillation of one set of particles has a huge impact on neighboring particles c) particles become too close together as they bump into each other making it more likely to hit other particles down the line

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?