Answer:
-6N
Explanation:
The force to the east is acting in the positive x-direction therefore it is positive. The force to the east is in the negative x-direction therefore it is negative. The net force is just the sum of the two so 3-9=-6
They are dynamic, with winds and waves constantly reworking and moving
the barrier island sand.
Changes in sea level also affect these islands.
Most scientists agree that sea level has been gradually rising over the
last thousand years, and this rise could be accelerating today due to global warming.
Rising sea level causes existing islands to migrate shoreward.
Answer: the minimal force that you need to apply to move the bureau is F = 198.45N
Explanation:
If you want to move an object, you need to apply a force that is bigger than the force of the statical friction.
The force of statical friction can be written as.
Ff = k*N
where k is the coefficient of static friction, in this case, k = 0.45, and N is the normal force between the object and the surface.
In this case, the normal force is the weight of the bedroom bureau, this is:
N = m*g = 45kg*9.8m/s^2 = 441N
Then the force is:
Fr = 0.45*441N = 198.45N
This means that the minimal force that you need to apply to move the bureau is F = 198.45N
and after this point, the force of friction will work wit the kinetic coefficient of friction, that usually is smaller than the statical one.
Answer:
Explanation:
A.
Given:
Vo = 21 m/s
Vf = 0 m/s
Using equation of Motion,
Vf^2 = Vo^2 - 2aS
S = (21^2)/2 × 9.8
= 22.5 m.
B.
Given:
S = 22.5 + 21 mm
= 22.521 m
Vo = 0 m/s
Using the equation of motion,
S = Vo × t + 1/2 × a × t^2
22.521 = 0 + 1/2 × 9.8 × t^2
t^2 = (2 × 22.521)/9.8
= 4.6
t = 2.14 s