Answer:
Explanation:
Mass =11.2kg
Constant velocity =3.3m/s
μk=0.25
Since the body is moving in constant velocity, then the acceleration is zero(0).
ΣF = Σ(ma)
The normal force acting on the body is upward and the weight is acting downward
Then ΣFy=0
Therefore, N=W
W=mg=11.2×9.8=109.76N
So, N=W=109.76N
Frictional force is given as
Fr=μkN
Fr=0.25×109.76
Fr=27.44N
Frictional force acting against the motion is 27.44N
Then the forward force moving the body forward
ΣF = Σ(ma)
Since a = 0
Then,
ΣF = 0
F-Fr=0
Then F=Fr
So the force moving the body forward is 27.44N
Answer:
a) fr = 266.92 N, fy = 1300 N, b) μ = 0.36
Explanation:
a) This is a balancing act.
Let's write the rotational equilibrium relations, where the turning point is the bottom of the ladder and the counterclockwise rotations are positive
-w x - W x₂ + R y = 0 (1)
usemso trigonometry to find distances
cos 60.08 = x / 7.5
x = 7.5 cos 60.08
x = 3.74 m
fireman
cos 60.08 = x₂ / 4
x2 = 4 cos 60
x2 = 2 m
wall support
sin 60.08 = y / 15
y = 15 are 60.08
y = 13 m
we substitute in equation 1
R y = w x + W x2
R = (w x + W x2) / y
R = (500 3.74 +800 2) / 13
R = 266.92 N
now let's write the expressions for the translational equilibrium
X axis
R -fr = 0
R = fr
fr = 266.92 N
Y Axis
Fy - w-W = 0
fy = 500 + 800
fy = 1300 N
b) ask the friction coefficient
the firefighter's distance is
cos 60.08 = x₃ / 9.00
x₃ = 9 cos 60
x₃ = 5.28 m
from equation 1
R = (w x + W x₃) / y
R = 500 3.74 + 800 5.28) / 13
R = 468.769 N
we saw that
fr = R = 468.769
The expression for the friction force is
fr = μ N
in this case the normal is the ratio to pesos
N = Fy
N = 1300 N
μ N = fr
μ = fr / N
μ = 468,769 / 1300
μ = 0.36
The food package will strike the ground at 11 degrees below the horizontal.
<h3>Time for the food package to hit the ground</h3>
The time for the food package to hit the ground is calculated as follows;
h = vt + ¹/₂gt²
<em>let the initial velocity be horizontal</em>
4900 = 0(t) + (0.5 x 9.8)t²
4900 = 4.9t²
t² = 4900/4.9
t² = 1,000
t = √1,000
t = 31.62 s
<h3> Final speed of the food package when it hits ground</h3>
vf(y) = vo + gt
vf(y) = 0 + (31.62 x 9.8)
vf(y) = 309.88 m/s
<h3>Angle of projection</h3>
The horizontal component of the speed will be constant, while vertical component will change

Angle below the horizontal = 90 - 79 = 11⁰
Thus, the food package will strike the ground at 11 degrees below the horizontal.
Learn more about angle of projection here: brainly.com/question/10671136
Answer:
Please show the warning's
Explanation:
The net force is 270 N
Explanation:
We can solve this problem by using Newton's second law, which states that the net force on an object is equal to the product between its mass and its acceleration:

where
F is the force
m is the mass
a is the acceleration
In this problem, we have
m = 90.0 kg

Substituting, we find the net force on the object:

Learn more about Newton's second law:
brainly.com/question/3820012
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