A bucket crane consists of a uniform boom of mass
M = 201 kg and length L= 59.05 ft that pivots at a point on
the bed of a fixed truck. The truck supports an elevated bucket
with a worker inside at the other end of the boom, as shown in
the figure. The bucket and the worker together can be modeled
as a point mass of weight 201 lb located at the end point of
the boom.
Suppose that when the boom makes an angle of 68.7° with the
horizontal truck bed, the bucket crane suddenly loses power,
causing the bucket and boom to rotate freely toward the
ground. Find the magnitude of the angular acceleration la of
the system just after the crane loses power. Take the rotation
axis to be at the point where the boom pivots on the truck bed.
Use g = 9.81 m/s2 for the acceleration due to gravity. For unit
conversions, assume that 1 m = 3.28 ft and 1 lb = 4.45 N.
Express your answer to at least two decimal places.
Answers
Newton's second law for rotational motion allows finding the results for the angular acceleration of the system at the moment of losing power is:
α =0.616 rad / s²
Newton's second law for rotational motion relates the torque to the moment of inertia and the angular acceleration, in the special case where the angular acceleration is zero, it is called the rotational equilibrium condition.
[tex]\sum \tau = I \alpha[/tex]
[tex]\tau = F \ r \ sin \theta[/tex]
where τ is the torque, F is the force, r the distance to the pivot point and θ the angle between the force, the distance, I is the moment of inertia and α is the angular acceleration.
In this case they indicate the values in several different units, let's reduce to the international system of measurements (SI).
Beam mass M = 201 kg Beam length L= 59.05 ft (1m / 3.28 ft) = 18.0 m Worker and basket weight Wh = 201 lb (1N / 0.2248 lb) = 894.1 N Beam angle tea = 68.7º
We place our reference system at the base of the beam on the truck and counterclockwise turns as positive, and in the attached we see a free-body diagram of the system.
[tex]W_m \ L \ sin 68.7 + Mg \ \frac{L}{2} \ sin 68.7 = I \alpha[/tex]
The moment of inertia is an additive scalar quantity, the total moment of inertia is the moment of inertia of the pen plus the moment of inertia of the man.
Moment of inertia of the beam with respect to one end.
[tex]I_[/tex] = ⅓ ML²
moment of inertia of man
[tex]I_m = M_m L^2[/tex]
Let's substitute
[tex](W_m + \frac{Mg}{2} ) \ L \ sin 68.7 = (\frac{1}{3} M + m_m ) L^2 \alpha \\\alpha = \frac{(W_m + \frac{Mg}{2} ) sin 68.7 }{ (\frac{1}{3} M + m_m ) L }[/tex]
Let's calculate
The mass of man is
m = [tex]\frac{W_m}{g}[/tex]
m = 894.1 / 9.8
m = 91.2 kg
[tex]\alpha = \frac{(894.1 +2.1 \ 9.8 ) \ sin 68.7 }{ 18.0 ( \frac{201}{3} + 91 }[/tex]
α = 0.616 rad / s²
In conclusion using Newton's second law for rotational motion we can find the results for the angular acceleration of the system at the moment of losing power is 0.616 rad / s²
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Acceleration = (change in speed) / time for the change)
Acceleration = (50 m/s) / (12 s)
Acceleration = (4 and 1/6) m/s²
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it would get healthier considering the stuff we put into the air and weather
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A jumbo jet collides with a sparrow. If neither exerts a greater force of impact, which experiences greater acceleration and why
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The sparrow experiences a Much greater acceleration because of its smaller mass.
Explanation:
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A jet plane is traveling with a velocity of 720 kilometers/hour due north. There is a crosswind of 40 kilometers/hour from the east. Find the resultant velocity and the direction of the jet plane.
A.
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B.
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C.
721 kilometers/hour in the direction of 3.2° west of north
D.
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Answers
Answer:
Option c is correct v = 721 km/h θ = 3.2°
Explanation:
In pic is further explanation: A triangle means division
The magnitude of the velocity of the plane can be found by calculating the resultant of the two velocities:
R= [tex]\sqrt{(720km ÷ h^)^2 + (40km ÷ h)^2) = 721.1 km ÷ h}[/tex]
The direction can be found as follows:
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Answer:
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Explanation:
Plato
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Answer:
You can't use energy conservation when mass is removed. This has required energy that you are not taking into account.
Answer:
because some time it dose not need to be i equation becasue it is not need
Explanation:
two balls are dropped from rest and allowed to fall for 1 s and the other for 3 s, compare the distances they have fallen
Answers
distance traveled by 3 second ball ≈ 45m
distance traveled by 1 second ball ≈ 5m
Explanation:
Since the 2 balls started at rest, their v initial = 0, and since no other force is acting on them except for the gravitational force, they accelerate downwards at 10m/s2.
To calculate the distance traveled by both balls, we apply the second formula of UARM motion:
• Δx = 1/2(a)(t^2) + (v0)(t)
Applying both 1s and 3s in this formula will yield you 5m and 45m respectively.
Hope this helps, brainliest would be appreciated :)
giải giúp em bài này với ạ?
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vdjs vs jsbdjskshskjsjdjfodjshsvsjsbdbdn
How does the appearance of spiral galaxies vary? *Select the two correct answers.*
A. They vary in how tightly their arms are wound.
B. They vary in the brightness of stars located on their arms.
C. Some are more elongated in shape than others.
D. Some have a band of stars and materials through their middle, but others do not
Answers
Answer:
A. And D.
A. They vary in how tightly their arms are wound.
D. Some have a band of stars and materials through their middle, but others do not.
The appearance of spiral galaxies vary in the following ways:
A. They vary in how tightly their arms are wound.
D. Some have a band of stars and materials through their middle, but others do not
Spiral galaxies are the galaxies where the gas clouds and the stars are concentrated in spiral arms.
Examples of spiral galaxies include Milky way, Sunflower Galaxy, Andromeda Galaxy, etc.
It should be noted that spiral galaxies vary in how tightly their arms are wound while some have a band of stars and materials through their middle, but others do not.
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Which of the following is a product in the process of photosynthesis?
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Answer:
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Answer:
push,weight,friction
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how can you increase the sensitivity of a Mercury thermometer?
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The sensitivity of a mercury thermometer can be increased by using a smaller mercury bulb, thinner wall and smaller bore. A smaller bulb contains less mercury and hence absorbs heat in shorter time. As a result it can response faster to temperature change.
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Answer:
4 filter funnel 7 round bottom flask sorry but that is all I know
The function of which system is to release energy from food for cells to use and to take oxygen into the blood and to remove carbon dioxide?
Digestive
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For question 51, do you use a=d/t
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No. That won't help. It's not even true.
A crane lifts 1800kg mass through a vertical height of 6cm in 9 seconds, Taking (g) as 10N/kg. what is the cranes power output?
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Explanation:
power output=(1800×10×0.06)/9=120watts
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Answer:
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Which of the following is the best hypothesis
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Answer:
Melting and frezzing are physical changes
A roller coaster has a mass of 585 kg when fully loaded with passengers.
A)If the vehicle has a speed of 18.0 m/s at point a, what is the force (in N) of the track on the vehicle at this point?
B) What is the maximum speed (in m/s) the vehicle can have at point B in order for gravity to hold it on the track?
Point A says the radius is 10m. Point B says radius is 15m.
Answers
Answer:
Explanation:
I'm going to ASSUME that point A is at the bottom of a circular curve.
The track must support the weight of the car and also supply the needed centripetal force
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I'm going to ASSUME that point B is at the top of a circular curve.
The track must support the weight of the car and also supply the needed centripetal force.
At a minimum, the weight can be reduced to zero and all the gravity acceleration acts as centripetal acceleration.
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What is the pulling force of this train, if its engine provides 4200 kW power and 90 km/h speed?
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Answers
The frequency of rotation of Mars is 0.0000113 Hertz.
Given the following data:
Period = 1 day and 37 minutes.To find the frequency of rotation in Hertz:
First of all, we would convert the the value of period in days and minutes to seconds because the period of oscillation of a physical object is measured in seconds.
Conversion:
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1477 minute = X seconds
Cross-multiplying, we have:
[tex]X = 60[/tex] × [tex]1477[/tex]
X = 88620 seconds
Now, we can find the frequency of rotation of Mars by using the formula:
[tex]Frequency = \frac{1}{Period}\\\\Frequency = \frac{1}{88620}[/tex]
Frequency of rotation = 0.0000113 Hertz
Therefore, the frequency of rotation of Mars is 0.0000113 Hertz.
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Because doing so can be used through scientific method<3
con lắc lò xo có m=0,6KG K=30N/m cho nó giao động điều hòa với biên độ 6cm tính thế năng động năng của con lắc khi x=4CM
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hdsjdjsksksjjdjd
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Answer:
Explanation:
N = mg = (1.00 + 0.500)(9.81) = 14.7 N
The magnitude of the normal force exerted on book A by the table is 14.7 N
ForcesFrom the question, we are to determine the magnitude of the normal force.
The normal force ca be calculated by using the formula
[tex]F_{n} = mg[/tex]
Where [tex]F_{n}[/tex] is the normal force
m is the mass
and g is the gravitational field strength ( g = 9.8 m/s²)
The mass will be addition of the masses since Book B is placed on top of the book.
Thus,
m = 1.00 kg + 0.500 kg = 1.50 kg
Then,
[tex]F_{n} = 1.5 \times 9.8[/tex]
[tex]F_{n} = 14.7 \ N[/tex]
Hence, the magnitude of the normal force exerted on book A by the table is 14.7 N
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Answer:
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how did the Ojibwe protect walleye populations?
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b.) did you Spears to catch walleye.
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d.) they said a limit on the number and size of Walleye a spearfisher can catch.
Answers
The Ojibwe protected walleye populations as D. They said a limit on the number and size of Walleye a spearfisher can catch.
Wisconsin Walleye War was a series of protests regarding the fishing and hunting rights of the Ojibwes. Wisconsin wanted to regulate the rights of the people whenever they went fishing and hunting.
The protest eventually led to the state speaking to the people. This resulted in a resolution that there should be a limit on the number and size of Walleye a spearfisher can catch.
This was necessary in order to preserve the walleye for future generations.
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Submit a hand-drawn picture by you of the following.
"Humpty Dumpty sat on a wall, Humpty Dumpty had a great fall, and all the king's horses and all the king's
men couldn't put Humpty Dumpty back together again."
Please help, thanks.
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A small heat engine has an energy input of 1,176 joules, and does 201 joules of work. What is the efficiency of the engine? (round your answer to the nearest whole number percent, but leave off the % symbol)
so, if you calculate it is 13.3%, enter your number as 13.
Answers
The efficiency of the engine is 17%.
Given the following data:
Energy input = 1,176 JoulesEnergy output = 201 JoulesTo find the efficiency of the engine:
Mathematically, the efficiency of an engine is calculated by using the formula:
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Where:
Eo is the energy output.Ei is the energy input.Substituting the given parameters into the formula, we have;
[tex]Efficiency = \frac{201}{1176}[/tex] × [tex]100[/tex]
[tex]Efficiency = 0.171[/tex] × [tex]100[/tex]
Efficiency = 17%
Therefore, the efficiency of the engine is 17%.
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answer the question below
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Answer:
1. Shield volcano
Runny,basaltic magma with low silica and low gas content. Has a broad,low profile.
2. Cinder cone volcano
Thick viscosity andesitic magma with high silica content and high gas content. Rapidly solidifying lava forms high,steep-sided cones.
3. Composite volcano
Medium viscosity rhyolitic magma with medium silicon content and medium gas content.Have flatter domes called cones.
Explanation:
Hope it helps you..
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