Answer: d= 0.57* l
Explanation:
We need to check that before ladder slips the length of ladder the painter can climb.
So we need to satisfy the equilibrium conditions.
So for ∑Fx=0, ∑Fy=0 and ∑M=0
We have,
At the base of ladder, two components N₁ acting vertical and f₁ acting horizontal
At the top of ladder, N₂ acting horizontal
And Between somewhere we have the weight of painter acting downward equal to= mg
So, we have N₁=mg
and also mg*d*cosФ= N₂*l*sin∅
So,
d=
* tan∅
Also, we have f₁=N₂
As f₁= чN₁
So f₁= 0.357 * 69.1 * 9.8
f₁= 241.75
Putting in d equation, we have
d= 
* tan 58
d= 0.57* l
So painter can be along the 57% of length before the ladder begins to slip
Omitting the 1 will not change the value of the number, but will change the units at the end of the problem
Answer:
D) True. This is what creates the body weight
Explanation:
Let's write Newton's second law for this case. For inclined planes the reference system takes one axis parallel to the plane (x axis) and the other perpendicular to the plane (y axis)
X axis
Wx -fr = ma
Y Axis
N - Wy = 0
With trigonometry we can find the components of weight
sin θ = Wₓ / W
cos θ = 
/ W
Wₓ = W sin θ
= W cos θ
W sin θ - fr = ma
From this expression as it indicates that the body is descending the force greater is the gravity that create the weight of the body
Let's examine the answers
A False This force does not apply because it is not a spring
B) False. It is balanced at all times with the component (Wy) of the weight
C) False. For there to be a rope, if it exists you should be less than the weight component for the block to lower
D) True. This is what creates the body weight
E) False. The cutting force occurs for force applied at a single point and gravity is applied at all points
If we assume that the acceleration is constant, we can use on the kinematic equations:
Vf = Vi + a*t = 15 + 3*4 = 27 m/s
A geocentric system is a part of the astronomical theory which describes the universe. Meaning that it puts the Earth in the CENTER of the universe as a point of view for other objects surrounding it.
