Calculate the electrical energy expended in a device across which the circuit voltage drops by 20.0 volts in moving a charge of 4 coulombs.
A)5 J
B)80 J
C)0.2 J

What if? physicists often measure the momentum of subatomic particles moving near the speed of light in units of mev/c, where c is the speed of light, and 1 mev = 1.6 ✕ 10−13 kg · m2/s2. based on this, what are the units of momentum for a high-speed subatomic particle in terms of fundamental si units?

8. why do radio telescopes convert radio waves (analog signals) to electrical (digital) signals for analysis? (hint: what did the article say about the advantages of digital signals? )

What is the magnitude of the acceleration vector which causes a particle to move from velocity −5i−2j m/s to −6i+ 7j m/s in 8 seconds. answer in m/s.