Answer:
B ) Ascend using my buddy alternative air source / make an emergency Ascent
Explanation:
From the description it can be seen his buddy is close by of which he can easily use the alternative air source. Also we can see that he is closer to the water surface than his buddy, of which controlled emergency swimming ascent is highly favourable in this condition.
Answer:
x = 1,185 m
, t = 4/3 s
, F = - 4 N
Explanation:
For this exercise we use Newton's second law
F = m a = m dv /dt
β - α t = m dv / dt
dv = (β – α t) dt
We integrate
v = β t - ½ α t²
We evaluate between the lower limits v = v₀ for t = 0 and the upper limit v = v for t = t
v-v₀ = β t - ½ α t²
the farthest point of the body is when v = v₀ = 0
0 = β t - ½ α t²
t = 2 β / α
t = 2 4/6
t = 4/3 s
Let's find the distance at this time
v = dx / dt
dx / dt = v₀ + β t - ½ α t2
dx = (v₀ + β t - ½ α t2) dt
We integrate
x = v₀ t + ½ β t - ½ 1/3 α t³
x = v₀ 4/3 + ½ 4 (4/3)² - 1/6 6 (4/3)³
The body comes out of rest
x = 3.5556 - 2.37
x = 1,185 m
The value of force is
F = β - α t
F = 4 - 6 4/3
F = - 4 N
Answer:
42 degrees, virtual image, same size as the object (26 cm)
Explanation:
The law of reflection states that:
- When a ray of light is incident on a flat surface (such as the plane mirror), the angle of reflection is equal to the angle of incidence
So, since in this case the angle of incidence is 42 degrees, the angle of reflection is also 42 degrees.
Moreover, the image formed by a plane mirror is always:
- Virtual (on the same side as the object)
- The same size as the object
So in this case, since the object's size is 26 cm, the image's size is also 26 cm.
