Answer:
11.6 s
Explanation:
We can use equation of motiom to solve this

Answer:
j
Explanation:
x = 4 t^2 - 2 t - 4.5
Position at t = 3 s
x = 4 (3)^2 - 2 (3) - 4.5 = 25.5 m
Velocity at t = 3 s
v = dx / dt = 8 t - 2
v ( t = 3 s) = 8 x 3 - 2 = 22 m/s
Acceleration at t = 3 s
a = dv / dt = 8
a ( t = 3 s ) = 8 m/s^2
When is the velocity = 0
v = 0
8 t - 2 = 0
t = 0.25 second
When is the position = 0
x = 0
4 t^2 - 2 t - 4.5 = 0

t = 1.4 second
The final velocity of the object is 16m\s.
Hope this helps! :)
Answer:
a) 
b) 
c) The wall may not be under steady because the two surfaces of the wall are exposed to the air at different temperatures and they have different convective coefficient.
Explanation:
Given:
- temperature of the inner surface of the wall,

- temperature of the outer surface of the wall,

- temperature of the air outside,

- temperature of the air inside,

- coefficient of heat convection on outside,

- coefficient of heat convection on inside,

a)
The heat flux between the interior air and the wall:
The convective heat transfer rate is given as,




b)
The heat flux between the exterior air and the wall:



c)
The wall may not be under steady because the two surfaces of the wall are exposed to the air at different temperatures and they have different convective coefficient.
The strain energy stored in a linear spring is
SE = (1/2)*k*x²
where
k = the spring constant
x = the extension (or compression) of the spring
Given:
k = 470 N/m
x = 17.0 cm = 0.17 m
Therefore
SE = 0.5*(470 N/m)*(0.17 m)² = 6.7915 J
Answer: 6.8 J (nearest tenth)