Answer:
When the velocity doesn't change its direction
Explanation:
Since velocity vector has 2 components: direction and magnitude, and speed is the velocity's magnitude. So if the velocity doesn't change its direction, we essentially use its magnitude, aka speed, to calculate the rate of change for acceleration.
You're fishing for "polarization".
Answer:
a) The velocity is 2.94m/s
b) 0.441
Explanation:
a) Assume gravity is 9.8m/s^2
Use the equation below to solve for the velocity at 0.30 seconds
,
vf =unknown velocity vi= initial velocity vi=0m/s a= 9.8m/s^2 t=0.30seconds
Step 1: Substitute the variables with the knowns

Step 2: Solve

b)
Use the equation below to solve for the displacement at 0.30 seconds

Step 1: Substitute the same variables with the knowns

Note that vi*t=0 as vi=0m/s
Step 2: Solve
x=0.441m
Its called gauge pressure