<span>In Coulomb's law, however, the
magnitude and sign of the electric force are determined by the electric
charge, rather than the mass, of an object. ... Thus, two negative
charges repel one another, while a positive charge attracts a negative
charge. The attraction or repulsion acts along the line between the two charges</span>
Answer:
b. the amount of electric charge that passes within a certain amount of time
Answer:
The speed of the baseball is approximately 19.855 m/s
Explanation:
From the question, we have;
The frequency of the microwave beam emitted by the speed gun, f = 2.41 × 10¹⁰ Hz
The change in the frequency of the returning wave, Δf = +3190 Hz higher
The Doppler shift for the microwave frequency emitted by the speed gun which is then reflected back to the gun by the moving baseball is given by 2 shifts as follows;


Where;
Δf = The change in frequency observed, known as the beat frequency = 3190 Hz
= The speed of the baseball
c = The speed of light = 3.0 × 10⁸ m/s
f = The frequency of the microwave beam = 2.41 × 10¹⁰ Hz
By plugging in the values, we have;


The speed of the baseball,
≈ 19.855 m/s