1. A person pulls on a two mass system, connected by a massless string, with a force (FA ) so that the net-acceleration (a) on the system is 7.0 m/s2 down the right slope. The coefficient of friction for the surface m1= 13.0kg is on is k=0.60, while m2= 3.0kg travels along a frictionless surface. m1 = 70 degrees and m2=38.

The intensity, or loudness, of a sound can be measured in decibels (db), according to the equation , where i is the intensity of a given sound and is the threshold of hearing intensity. what is the intensity, in decibels, [i(db)], when ? use a calculator. round to the nearest whole number. 8 9 19 80

First, launch the video below. you will be asked to use your knowledge of physics to predict the outcome of an experiment. then, close the video window and answer the question at right. you can watch the video again at any point. part a as in the video, we apply a charge +q to the half-shell that carries the electroscope. this time, we also apply a charge –q to the other half-shell. when we bring the two halves together, we observe that the electroscope discharges, just as in the video. what does the electroscope needle do when you separate the two half-shells again? view available hint(s) as in the video, we apply a charge + to the half-shell that carries the electroscope. this time, we also apply a charge – to the other half-shell. when we bring the two halves together, we observe that the electroscope discharges, just as in the video. what does the electroscope needle do when you separate the two half-shells again? it deflects more than it did at the end of the video. it deflects the same amount as at end of the video. it does not deflect at all. it deflects less than it did at the end of the video. submit

Waves are used in many practical applications to support work, entertainment, and health. one example is the use of ultrasound imaging to safely track the development of a growing fetus. what is a specific example of a practical application of waves in medicine, entertainment, safety, or other fields? provide a brief explanation of how the properties of waves are useful to that application.