A certain object is subject to two forces: a 10-N force straight up and a 10-N force straight down. A student states that since both forces are in the vertical direction, the object cannot be moving horizontally. Why is this an incorrect conclusion? A.
The vertical forces are balanced.
B.
Vertical net forces can cause horizontal motion.
C.
A horizontal force is not required for horizontal movement.
D.
Two vertical forces can combine to form a horizontal resultant force.

c. magnitude and direction

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

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