A 125 kg mail bag hangs by a vertical rope 3.3 m long. A postal worker then displaces the bag to a position 2.2 m sideways from its original position, always keeping the rope taut.
1) What horizontal force is necessary to hold the bag in the new position?
2) As the bag is moved to this position, how much work is done by the rope?
3) As the bag is moved to this position, how much work is done by the worker?
Answers
Answer:
1) the required horizontal force F is 1095.6 N
2) W = 0 J { work done by rope will be 0 since tension perpendicular }
3) work is done by the worker is 1029.4 J
Explanation:
Given that;
mass of bag m = 125 kg
length of rope [tex]l[/tex] = 3.3 m
displacement of bag d = 2.2 m
1) What horizontal force is necessary to hold the bag in the new position?
from the figure below; ( triangle )
SOH CAH TOA
sin = opp / hyp
sin[tex]\theta[/tex] = d / [tex]l[/tex]
sin[tex]\theta[/tex] = 2.2/ 3.3
sin[tex]\theta[/tex] = 0.6666
[tex]\theta[/tex] = sin⁻¹ ( 0.6666 )
[tex]\theta[/tex] = 41.81°
Now, tension in the string is resolved into components as illustrated in the image below;
Tsin[tex]\theta[/tex] = F
Tcos[tex]\theta[/tex] = mg
so
Tsin[tex]\theta[/tex] / Tcos[tex]\theta[/tex] = F / mg
sin[tex]\theta[/tex] / cos[tex]\theta[/tex] = F / mg
we know that; tangent = sine/cosine
so
tan[tex]\theta[/tex] = F / mg
F = mg tan[tex]\theta[/tex]
we substitute
Horizontal force F = (125kg)( 9.8 m/s²) tan( 41.81° )
F = 1225 × 0.8944
F = 1095.6 N
Therefore, the required horizontal force F is 1095.6 N
2) As the bag is moved to this position, how much work is done by the rope?
Tension in the rope and displacement of mass are perpendicular,
so, work done will be;
W = Tdcos90°
W = Td × 0
W = 0 J { work done by rope will be 0 since tension perpendicular }
3) As the bag is moved to this position, how much work is done by the worker
from the diagram in the image below;
SOH CAH TOA
cos = adj / hyp
cos[tex]\theta[/tex] = ([tex]l[/tex] - h) / [tex]l[/tex]
we substitute
cos[tex]\theta[/tex] = ([tex]l[/tex] - h) / [tex]l[/tex] = 1 - h/[tex]l[/tex]
cos[tex]\theta[/tex] = 1 - h/[tex]l[/tex]
h/[tex]l[/tex] = 1 - cos[tex]\theta[/tex]
h = [tex]l[/tex]( 1 - cos[tex]\theta[/tex] )
now, work done by the worker against gravity will be;
W = mgh = mf[tex]l[/tex]( 1 - cos[tex]\theta[/tex] )
W = mf[tex]l[/tex]( 1 - cos[tex]\theta[/tex] )
we substitute
W = (125 kg)((9.8 m/s²)(3.3 m)( 1 - cos41.81° )
W = 4042.5 × ( 1 - 0.745359 )
W = 4042.5 × 0.254641
W = 1029.4 J
Therefore, work is done by the worker is 1029.4 J
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Answer:
Weight
Explanation:
We call it "Ralph" or "the object's weight".
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A transverse wave is represented below. 1.5 m 0.20 m What is the approximate amplitude and wavelength of the wave? amplitude = 0.20 m, wavelength = 0.60 m B. amplitude = 0.20 m, wavelength = 0.30 m C. amplitude = 0.10 m, wavelength = 0.60 m OO amplitude = 0.10 m, wavelength = 0.30 m
Answers
Answer:
C. amplitude = 0.10 m, wavelength = 0.60 m
Explanation:
The diagram shows an oscillating progressive wave, with its amplitude and wavelength.
Amplitude of a wave is the maximum distance covered either upward or downward.
So that,
amplitude of the wave, A = [tex]\frac{0.2}{2}[/tex]
= 0.1
Amplitude of the wave = 0.1 m
Wavelength in this case is the distance from crest to crest, or trough to trough of the wave.
So that,
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Therefore, the amplitude of the wave is 0.10 m, while the wavelength is 0.60 m.
At the bottom of the air track, the glider hits and stretches a rubber band, that causes the glider to change direction. When the rubber band is maximally stretched, the glider's kinetic energy is zero, because it is momentarily at rest. Since the glider is at the bottom of the air track, its (gravitational) potential energy is also zero. So the sum of the kinetic energy and gravitational potential energies is zero, yet energy is conserved. Where did the energy go?
Answers
Answer:
That energy is the elastic potential energy of the rubber band. At the bottom position, all the energy is being stored in the stretched rubber band, in the form of elastic potential energy.
Explanation:
When the glider reaches the bottom, its kinetic energy and potential energy become zero due to zero velocity and zero height, respectively. So, the sum of these energies will become zero. This will violate the law of conservation f energy. Hence, there must be a third type of energy that accounts for the conservation of the energy of the system at other configurations.
That energy is the elastic potential energy of the rubber band. At the bottom position, all the energy is being stored in the stretched rubber band, in the form of elastic potential energy.
A flat loop of wire consisting of a single turn of cross-sectional area 8.80 cm2 is perpendicular to a magnetic field that increases uniformly in magnitude from 0.500 T to 1.80 T in 1.10 s. What is the resulting induced current if the loop has a resistance of 2.20
Answers
Answer:
The magnitude of the induced current is 4.73 x 10⁻³ A.
Explanation:
Given;
number of turns, N = 1
cross sectional area of the loop, A = 8.8 cm² = 8.8 x 10⁻⁴ m²
change in magnetic field strength, ΔB = 1.8 T - 0.5 T = 1.3 T
change in time, Δt = 1.10 s
resistance of the loop, R = 2.2 ohm
The magnitude of the induced emf is calculated as;
[tex]emf = \frac{NA \Delta B}{\Delta t} \\\\emf = \frac{1 \times 8.8\times 10^{-4} \times 1.3}{1.10} \\\\emf = 1.04 \times 10^{-3} \ V[/tex]
The induced current in the loop is calculated as;
[tex]I = \frac{emf}{R} \\\\I = \frac{1.04 \times 10^{-3}}{2.2} \\\\I= 4.73 \times 10^{-4} \ A[/tex]
Therefore, the magnitude of the induced current is 4.73 x 10⁻³ A
If a person walks 3 m north and 5 meters east, how would you find the displacement for that person? what would the displacement be?
Answers
Answer:
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⇒displacement=16+9−−−−−√=25−−√=5m
The course an object travels along is called DIRECTION.
A
TRUE
B
FALSE
DO NOT WRITE DOWN NONSENSE OR YOU WILL BE REPORTED!!!!!!!!
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What factors determine electric potential?
A. Mass and distance
B. Charge and density
C. Charge and distance
O D. Mass and charge
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Answer: C. Charge and distance
How is it difficult to perform electrostatic experiments on humid days
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Answer:
that should be the right answer
An object is spun in a circle of radius 1.5m with a frequency of 6.0Hz. what is it’s velocity ?
Answers
Answer:
56.55 m/s
Explanation:
Frequency=1/T
1/6 = 0.1666666
V=(2*pi*1.5)/0.166666
PLEASE HELP WITH THIS ONE QUESTION
A bird lands on a bird feeder which is connected to a spring. The mass of the bird is exactly the same as the mass of the bird feeder. How does the added mass affect the period of oscillation of the bird feeder?
The period is less, but not halved.
The period is more, but not doubled.
The period is halved.
The period is doubled.
Answers
Answer:
The period is more, but not doubled.
Explanation:
Recall that the period of a mass on a spring is T=2πmk.
why type of volcano is built almost entirely from ejected lava fragments
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Answer:
Shield volcanoes
Explanation:
In 1666 at the age of 23, what scientist
developed the theories of gravitation inspired
by an apple falling from a tree?
A. Galileo Galilei
B. Issac Newton
C. Albert Einstein
D. Nicolaus Copernicus
Answers
Answer:
B - Isaac NewtonExplanation:
He first thought of his system of gravitation which he hit upon by observing an apple fall from a tree,
The incident occurring in the late summer of 1666.
4. When you are holding a book, energy is stored between the book and the Earth.
This type of energy is called
potential energy.
A. Elastic potential energy
B. Chemical potential energy
C. Gravitational potential energy
D. Kinetic energy
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Answer:
gravitational potential energy
I want answer plzz??
Answers
Answer:
a=0.5g ms^-2
Explanation:
Let tension be T
acceleration be a
g be gravitational acceleration 9.81ms^-2
They share same T and a
by force diagram the net force on m:
T-2.1g=2.1a
net force on M:
6.3g-T=6.3a
solve:
(T-2.1g)/(6.3g-T)=2.1a/6.3a
3T+T=12.6g
T=3.15g newton
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a=0.5g ms^-2
Due to historical difficulty in delivering supplies by plane, one of your colleagues has suggested you develop a catapult for slinging supplies to affected areas, similar to the electromagnetic lift catapults used to launch planes from aircraft carriers. This catapult is located at a fixed point 400 meters away and 50 meters below the target site. The catapult is capable of launching the payload at 67 meters per second and an initial launch angle of 50 degrees. Using your knowledge of kinematics equations, determine whether this would be sufficient to deliver the payload to the drop site.
Answers
Answer:
Please see below as the answer is self-explanatory.
Explanation:
We can take the initial velocity vector, which magnitude is a given (67 m/s) and project it along two directions perpendicular each other, which we choose horizontal (coincident with x-axis, positive to the right), and vertical (coincident with y-axis, positive upward).Both movements are independent each other, due to they are perpendicular.In the horizontal direction, assuming no other forces acting, once launched, the supply must keep the speed constant.Applying the definition of cosine of an angle, we can find the horizontal component of the initial velocity vector, as follows:[tex]v_{avgx} = v_{o}*cos 50 = 67 m/s * cos 50 = 43.1 m/s (1)[/tex]
Applying the definition of average velocity, since we know the horizontal distance to the target, we can find the time needed to travel this distance, as follows:[tex]t = \frac{\Delta x}{v_{avgx} } = \frac{400m}{43.1m/s} = 9.3 s (2)[/tex]
In the vertical direction, once launched, the only influence on the supply is due to gravity, that accelerates it with a downward acceleration that we call g, which magnitude is 9.8 m/s2.Since g is constant (close to the Earth's surface), we can use the following kinematic equation in order to find the vertical displacement at the same time t that we found above, as follows:[tex]\Delta y = v_{oy} * t - \frac{1}{2} *g*t^{2} (3)[/tex]
In this case, v₀y, is just the vertical component of the initial velocity, that we can find applying the definition of the sine of an angle, as follows:[tex]v_{oy} = v_{o}*sin 50 = 67 m/s * sin 50 = 51.3 m/s (4)[/tex]
Replacing in (3) the values of t, g, and v₀y, we can find the vertical displacement at the time t, as follows:[tex]\Delta y = (53.1m/s * 9.3s) - \frac{1}{2} *9.8m/s2*(9.3s)^{2} = 53.5 m (5)[/tex]
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Answers
Answer:
v = 3.74 m/s
Explanation:
Given that,
The acceleration of the object in circular path, a = 0.4 m/s²
The radius of the circle, r = 35 m
We need to find the velocity of the object. The acceleration of an object on the circular path is given by :
[tex]a=\dfrac{v^2}{r}\\\\v=\sqrt{ar} \\\\v=\sqrt{0.4\times35}\\\\v=3.74\ m/s[/tex]
So, the velocity of the object is equal to 3.74 m/s.
In a transverse wave, the distance from any two consecutive crest or any two consecutive troughs is called the
Answers
Answer:
Wavelength
Explanation:
Answer:
Wavelength if it's the horizontal distance. Wave Height if it's vertical distance.
Explanation:
A wave with a frequency of 5Hz travels a distance of 40mm in 2 seconds.What is the speed of the wave
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Answer:
20mm per second
Explanation:
lol
What is the unique geological feature found on Mercury surface?
Answers
Answer:
The surface of Mercury has landforms that indicate its crust may have contracted. They are long, sinuous cliffs called lobate scarps. These scarps appear to be the surface expression of thrust faults, where the crust is broken along an inclined plane and pushed upward.
Explanation:
I hope this helps a little bit.
While sitting in a boat, a fisherman observes that 2 complete waves pass by his position every 4 seconds. What is the period of these waves?A)2s B)8s C) 0.5 s D) 4s
Answers
Answer:
2
Explanation:
Because 2 waves 4 secs means 1 in 2s
The period of these waves is 2s. and The right option is A)2s.
The period of a wave is the time taken by a wave to complete one cycle.
The formula of period from the question is given below.
⇒ Formula:
T = t/2.................... Equation 1⇒ Where:
T = Period of the wavet = time taken for two complete oscillationFrom the question,
⇒ Given:
t = 4 seconds.⇒ Substitute these value above into equation 1
T = 4/2T = 2 seconds.Hence, The period of these waves is 2s.
The right option is A)2s
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What is the magnitude of the force that is exerted on a 20 kg mass to give it an acceleration of 10.0
m/s2?
Answers
Answer:Mass of the body = 20 kg.
Final Velocity = 5.8 m/s.
Initial velocity = 0
Time = 3 seconds.
Using the Formula,
Acceleration = (v - u)/ t
= (5.8 - 0)/ 3
= 1.6 m /s².
Now, Using the Formula,
Force = mass × acceleration
= 20 × 1.6
=
Explanation: I REALLY HOPE THIS HELPS I'M KINDA NEW AT THIS :] :]
The magnitude of requires force, that is exerted on a 20 kg mass to give it an acceleration of 10.0 m/s^2 is 200 Newton.
What is force?The definition of force in physics is: The push or pull on a mass-containing item changes its velocity.
An external force is an agent that has the power to alter the resting or moving condition of a body. It has a direction and a magnitude. The application of force is the location at which force is applied, and the direction in which the force is applied is known as the direction of the force.
Given parameters:
Mass of the object: m = 20 kg.
Acceleration of the object: a = 10.0 m/s^2.
Hence, according to Newton's 2nd law of motion:
the magnitude of requires force = mass ×acceleration
= 20 × 10 Newton
= 200 Newton.
Hence, the magnitude of requires force is 200 Newton.
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I'm asking for a quick favor. I'm trying to understand an equation that has to do with Projectile motion, Bernoulli's principle, and Magnus Effect. Basically focused on understanding air resistance on a projectile. I would like to discuss this privately rather than have it on this public forum. I'll give you 100 of my points if you help.
Answers
Explanation:
Projectile motion, Bernoulli's principle, and Magnus Effect.
Sure I would be happy to discuss projectile motion!
I'll do it if you mark brainliest :) I need the points thanks
How fast is a ball going when it hits the ground after being dropped from a
height of 16 m? The acceleration of gravity is 9.8 m/s2
A. 22.5 m/s
B. 28.1 m/s
O C. 17.7 m/s
D. 19.3 m/s
Answers
Hi there!
[tex]\large\boxed{\text{C. 17.7m/s}}[/tex]
Use the following kinematic equation to solve:
vf² = vi² + 2(ad)
Since the initial velocity is 0 m/s because it started at rest, we can eliminate this part of the equation:
vf² = 2ad
Plug in the given acceleration and distance:
vf² = 2(9.8)(16)
vf ≈ 17.7. The correct answer is C.
what are three physical properties of gases
Answers
Answer: Gases have three characteristic properties: (1) they are easy to compress, (2) they expand to fill their containers, and (3) they occupy far more space than the liquids or solids from which they form. An internal combustion engine provides a good example of the ease with which gases can be compressed.
Explanation:
Two turtles are floating next to each other in a pond. One turtle has twice as much mass as the other turtle. The two turtles push off each other. Which statement correctly describes their resulting momenta?
a). The larger turtle has twice as much momentum.
b).The smaller turtle has twice as much momentum.
c).The turtles have the same momenta as one another.
d).The turtles each have negative values of momentum.
Answers
Answer:
B
Explanation:
the reason the small turtle has more momentum is because it was less an example is I have two rocks a rock that weighs 1 oz and another rock that weighs half a pound the one that is half a pound Falls faster in the one that weighs an ounce Falls last hopefully that makes sense
A scientist plans to release a weather balloon from ground level, to be used for high-altitude atmospheric measurements. The balloon is spherical, with a radius of 2.10 m, and filled with hydrogen. The total mass of the balloon (including the hydrogen within it) and the instruments it carries is 24.0 kg. The density of air at ground level is 1.29 kg/m3. (a) What is the magnitude of the buoyant force (in N) acting on the balloon, just after it is released from ground level
Answers
Answer:
Fb = 490.4 N
Explanation:
According to Archimedes' principle, any object submerged in a fluid, receives a push upward (which we call buoyant force) equal to the weight of the volume of the fluid removed by the object.We can express this force (Fb), in terms of the density and the volume of the fluid, as follows:[tex]F_{b} = \rho * V * g (1)[/tex]
The volume removed from the fluid by the balloon is just the volume of the balloon, assuming that it is a perfect sphere, as follows:[tex]V = \frac{4}{3}*\pi * R^{3} = \frac{4}{3} *\pi *(2.1m)^{3} = 38.8 m3 (2)[/tex]
Replacing by the givens and (2) in (1), we get:[tex]F_{b} = \rho * V * g = 1.29 kg/m3* 38.8m3*9.8m/s2 = 490.4 N (3)[/tex]
What happens when a moving object experiences no net force?
Answers
Answer:
An object with no net forces acting on it which is initially at rest will remain at rest. If it is moving, it will continue to move in a straight line with constant velocity. Forces are "pushes" or "pulls" on the object, and forces, like velocity and acceleration are vector quantities.
An object is moving with constant non-zero velocity. Which of thw following statements about it must be true
Answers
Answer:
The net force on the object is zero.
Explanation:
An object is moving with constant non-zero velocity. If velocity is constant, it means that the change in velocity is equal to 0. As a result, acceleration of the object is equal to 0. Net force is the product of mass and acceleration. Hence, the correct option is (d) "The net force on the object is zero".