What is the magnitude of the electric field at a point 0.0050 m from a 0.0040
C charge?
Use E = kg and k = 9.00 x 10°N. m/c?
A. 1.4 x 1072 N
B. 2.8 1012 N
C. 1.1 x 1010 N
D. 7.2×10°N

it's when something is going so fast it makes a loud noise, breaking the sound barrier, for example: a jet makes a loud noise, not only cause of the jet but because they reached a point where they went so fast that you can year the noise from various parts, kinda like a police car, lets say the car was going   so fast that you hear the siren of the cop car right next to you, but the car is probably a mile a way, it's cos the siren was next to you a few seconds if you understand me

b. false

explanation:

suppose a rock in free fall is dropped off a cliff. after falling for 5 seconds, its speed would not be 100 m/s.