A violinist is tuning her violin to 440Hz. She plays the note while listening to an electronically generated tone and hears 3Hz, which increases to 4Hz when she tightens the violin. What was the frequency of the note played by the violin when she heard the 3 Hz beats

The particle p starts from rest at point a at time t = 0 and changes its speed thereafter at a constant rate of 2.8g as it follows the horizontal path shown. determine the magnitude and direction of its total acceleration (a) just before point b, (b) just after point b, and (c) as it passes point c. state your directions relative to the x-axis shown (ccw positive) and choose the angle with the smallest magnitude.