Answer:
4. Downward and its value is constant
Explanation:
As this is a case of projectile motion, we use the reference frame where upward direction to be positive for 
, and in the same way to be negative in the downward direction. On another hand, we have that gravity is always acting this means that gravitational acceleration g is directed downward constantly over the dart not only during the upward but also during the downward part of the trajectory. And it is ruled by the following equations.
For the x-axis
For the y-axis
Where 
, is the initial velocity.
Answer:
This is due to bending of light ray passing through the medium.
Explanation:
This can be explained using the concept of refraction.
Refraction can be defined as the bending of light ray as it travels from one medium to another (it can be from the less dense to denser medium or denser to less dense medium)
For that of pencil in water, light ray travels from less dense medium(surrounding air) to denser medium(water). This causes the pencil to bend away from the normal rather than towards the normal (angle of refraction being greater than angle of incidence) and hence the reason for the bending.
NB: Normal line is perpendicular to the plane between the medium.
Where's the video? Hard to answer when we can't watch it bro...
Answer:
P1 = 0 gage
P2 = 87.9 lb/ft³
Explanation:
Given data
Airplane flying = 200 mph = 293.33 ft/s
altitude height = 5000-ft
air velocity relative to the airplane = 273 mph = 400.4 ft/s
Solution
we know density at height 5000-ft is 2.04 × 
slug/ft³
so here P1 + 
= P2 + 
and here
P1 = 0 gage
because P1 = atmospheric pressure
and so here put here value and we get
P1 + = P2 +
0 + 
solve it we get
P2 = 87.9 lb/ft³
