A particle is moving at a constant speed in a counterclockwise circle of radius r about the
point x = y = 0. At a certain instant it is at
x = −r, y = 0.
What is the direction of its acceleration at
that instant?
A. It is along ˆı.
B. It is along −ˆj.
C. It is along ˆj.
D. It is along −ˆı.

Which of the following statements comparing electron microscopy and light microscopy is false? which of the following statements comparing electron microscopy and light microscopy is false? both the electron microscope and the light microscope use the same wavelengths for illumination. images produced by light microscopes can be in color, whereas electron microscope images are black and white unless they are artificially colored. the electron microscope has greater resolution than the light microscope. electron microscopes can allow examination of viruses and internal cell structures, whereas light microscopes are limited to objects that are 0.5 micrometers and larger. request answer