Answer:
The rate at which work is done is power
A child, m = 25. 0 kg, swings from a rope, l = 9. 43 m, which hangs above water, d = 1. 9 m, when vertical. The child is h = 4. 8 m above the water when she begins to swing.
The velocity at the bottom of the swing is [tex]\mathbf{v= \sqrt{2gh -2gd}}[/tex]. The time it took the child to reach the river is 0.62 seconds.
The objective of this question is to determine:
The expression for the velocity of the child at the bottom of the swing.Suppose the child lets go at the bottom of the swing, how long does she take to reach the river at t seconds.At the bottom of the swing, there is an equal change in both the Kinetic energy as well as the potential energy and the expression can be computed as:
[tex]\mathbf{\dfrac{1}{2}mv^2 = mg (h -d)}[/tex]
[tex]\mathbf{\dfrac{v^2}{2}= g (h -d)}[/tex]
[tex]\mathbf{v^2= 2gh -2gd}[/tex]
[tex]\mathbf{v= \sqrt{2gh -2gd}}[/tex]
According to the second equation of motion;
[tex]\mathbf{S = ut +\dfrac{1}{2}at^2}[/tex]
where;
distance s = d = 1.9 macceleration due to gravity = 9.8 m/s²initial velocity (u) = 0∴
[tex]\mathbf{1.9 = 0(t) +\dfrac{1}{2}(9.8) t^2}[/tex]
[tex]\mathbf{1.9 = \dfrac{1}{2}(9.8) t^2}[/tex]
[tex]\mathbf{t^2 =\dfrac{1.9\times 2}{9.8} }}[/tex]
[tex]\mathbf{t = \sqrt{\dfrac{1.9\times2}{9.8}}}[/tex]
[tex]\mathbf{t =0.62 \ s}[/tex]
Therefore, we can conclude that the velocity at the bottom of the swing is [tex]\mathbf{v= \sqrt{2gh -2gd}}[/tex]. The time it took the child to reach the river is 0.62 seconds.
Learn more about velocity here:
https://brainly.com/question/13665920
I couldn't answer this question may someone please help me
Distance (s) =20 m
Initial velocity =0 m/s
g=10 m/s²
By using the formula:
v²= u²+ 2as
v²=0²+ 2×10×15
v²= 300
V= 10root over 3
[tex]10 \sqrt{3} [/tex]
For calculating time,
v= u+ at
10 root over 3 = 0+ 10t
10 root over= 10t
t = 1 root over 3
t = 1.73 s
[tex]1 \sqrt{3} [/tex]
The the stone will hit the ground with a velocity of 10 root over 3 m/s in 1 root over 3 sec.
The potential energy stored in the compressed spring of a dart gun, with a spring constant of 32. 50 N/m, is 0. 640 J. Find by how much is the spring is compressed.
The spring in the dart gun is compressed by 0.16 m
From the question given above, the following data were obtained:
Spring constant (K) = 50 N/m
Potential Energy (PE) = 0.640 J
Compression (e) =?The compression experience by the spring can be obtained as follow:
PE = ½ke²
0.64 = ½ × 50 × e²
0.64 = 25 × e²
Divide both side by 25
e² = 0.64 / 25
Take the square root of both side
e = √(0.64 / 25)
e = 0.16 m
Therefore, the spring is compressed by 0.16 m
Learn more: https://brainly.com/question/14848315
Which is the force that results from use of a machine?
O a. input force
Oc. input work
Ob. output force
Od. output work
Answer:
D. Output force
Explanation:
The input force is the effort used to run the machine and this results in an output force.
What is a thought experiment?
Answer:
A thought experiment is an experiment carried out only in the imagination
Explanation:
how have astronomers interpreted the unexpectedly fast rotation of galaxies
Answer:
There must be a lot of dark matter that can be felt but not seen
The astronomers interpreted the unexpectedly fast rotation of galaxies that there must be a large quantity of dark energy whose gravity is detectable yet invisible.
What is a galaxy?Any system of stars plus interstellar material that makes up the cosmos is referred to as a galaxy. Such assemblages are common, and many of them are so massive that they hold tens of trillions of stars.
A vast variety of galaxies, from dim, hazy dwarf objects to spectacular spiral-shaped giants, have been created by nature. Almost all galaxies seem to have formed shortly after the universe started, and they are everywhere in space, even at the farthest limits of the universe that can be seen by the most advanced telescopes.
The majority of galaxies are found in clusters, many of which are further organized into clusters that span hundreds of billions of light-years.
Since there are almost empty spaces between these so-called super clusters, the universe's overall structure resembles a network of sheets or chains of galaxies.
To know more about Galaxy:
https://brainly.com/question/2905713
#SPJ12
If you eat cheese are you 1 percent cheese?
Answer:
No. Exactly what you eat doesn’t make up your internal structure.
:)
Answer:
Explanation:
Light cheeses are less than 20 %, low fat cheeses are 20 to 30%, fat cheeses are 50 to 60%, double-cream cheeses are at least 60% and triple-cream cheeses are at least 75 %.
How much force is required to move a tractor 60m, when using 250J of work?
Answer:
Work done,W= 250J
Displacement , s = 60
We know that, Work done = Force x displacement
i.e , W = Fxs
250 J = F x 60m
F = 250/60
=4.16 N
Hence , 4.16 N of Force is applied on the body.
Please find attached photograph for your answer.
Hope it helps.
Do comment if you have any query.
PLEASE ANSWER THIS RIGHT ASAP
What is the correct definition of energy?
A: chemical changes
B: force × distance
C: both kinetic and potential energy
D: the ability to do work or cause change
Answer:
D: The ability to do work or cause change.
Explanation:
Energy can be defined as the ability to do work. We apply energy in basically everything we do in life, energy is needed to walk or move from one position to another, it is required to eat and do other basic things of life. The body system converts the food that is being consumed into energy, this energy can be switched from one form to another.
There are various forms of energy which include solar energy, wind energy, electrical energy, mechanical energy, kinetic energy, potential energy, etc. This form of energy can be converted from one form to another but cannot be destroyed.
Hope this helps :)
I need help quickly pls
Answer:
Ok I'm not 100% on this one but, try 3 lifes sorry if u get it wrong D:
Explanation:
PLEASE ANSWER NEED HELP!!!!!!!! PLEASE THE CORRECT ANSWER!!!!!!
Imagine that a car is speeding down the highway and it hits a large bump in the road that forces it off the road. What would Newton call that object?
A.
a physical object
B.
a course interrupter
C.
an unbalanced force
D.
an unfortunate event
PLEASE NO LINKS OR I WILL REPORT YOU
Answer:
C. unbalanced force
Explanation:
it is called unbalanced force because it has changed direction of the moving object
Help help fast please first answer gets brainiest also needs to be clearly stated
The right to gather to advance some political or social cause is known as
Answer:
the first amendment
Explanation:
the first amendment to the United States constitution allows the freedoms concerning religion, expression, assembly, and the right to gather and petition.
How much would a 70 kg student weigh on Pluto? (massPluto = 1.25 x 1022 kg, radiusPluto = 1.20 x 106 m)
Answer: the weight would be 4.6 (I think i don’t know))
Explanation:
PLS HELP ASAP it's just 2 questions and they are multiple choice!
5. How are electromagnetic waves similar to ocean waves?.
Answer:
Electromagnetic waves have crests and troughs similar to those of ocean waves. The distance between crests is the wavelength. The shortest wavelengths are just fractions of the size of an atom, while the longest wavelengths scientists currently study can be larger than the diameter of our planet!
Explanation:
hope it's helps u ...........!
if you were planning to escape from someone and you were tied to a chair what would you do
Leverrier predicted that an invisible planet was pulling the planet Uranus off its predicted course around the sun. Likewise, human beings are pulled off course by the invisible forces of their ____________.
Human beings are pulled off course as a result of the invisible forces of the unconscious.
According to Leverrier, he stated that an invisible planet was pulling the planet Uranus off its predicted course around the sun.
In such a way, human beings are pulled off course by the invisible forces of their unconscious minds. The unconscious minds of people control the thoughts of people.
Read related link on:
https://brainly.com/question/25588203
What acceleration occurs if the friction force in #4 is now 4N?
The acceleration of the 20 N force is 6.67 m/s^2. The acceleration of the 4N force is 1.33 m/s^2.
What is force?We define the force that acts on a body as that which is able to cause an acceleration or that which is able to change the direction of an object. Recall that from the Newton first law, an object would continue in its state of rest or uniform motion unless the object is acted upon by an external force.
Now the frictional force is the force that tends to resist the motion of two surfaces that are in contact. Owing to the fact that it is a resistive force its direction is always opposite the force that seeks to move the object forward.
Now;
F = ma
a = F/m
a = 20 N/3Kg
a = 6.67 m/s^2
If the force is 4N;
a = F/m
a = 4N/3Kg
a = 1.33 m/s^2
Learn more about acceleration:https://brainly.com/question/12550364
#SPJ1
Missing parts;
How would you calculate the acceleration if you push with a 20 N horizontal force on a 3 kg block on a horizontal friction-free air table? What is the acceleration if the friction force is 4 N?
A cyclist accelerates from 0m/s to 8m/s in 3 seconds.
Answer:
the rate of acceleration is 2.6666(and so on) if thats your question
Explanation:
The c-c sigma bond in acetylene is formed by the overlap of which two orbitals.
Answer:When carbon atom tends to form single bonds then its hybridization is , when carbon atom tends to form double bond then its hybridization is and when a carbon atom is attached to a triple bond or with two double bonds then its hydridization is sp.
For example, in HCN molecule there is a triple existing between the carbon and nitrogen atom.
So, hybridization of carbon in this molecules is sp. Moreover, nitrogen atom is also attached via triple bond and it also has a lone pair of electrons. Hence, the hybridization of nitrogen atom is also sp.
Thus, we can conclude that s and p type of orbitals overlap to form the sigma bond between C and N in H−C≡N:
Explanation:
which term is most applicable to a discussion of angular momentum in the context of black holes?
A: Photon
B: Curvature
C: Spin
D: Time
Answer:
c: spin
Explanation:
it's not curvature
The most applicable term to a discussion of angular momentum in the context of black holes is Spin. Thus, the correct option is C.
What is angular momentum of black holes?
Angular Momentum is defined as the property of any rotating object which is given by the product of the moment of inertia of an object and the angular velocity of the rotating object. Angular momentum is a vector quantity and it has both the magnitude and direction. The examples of angular momentum are the rotation and revolution of the Earth.
When the astronomers claim that they have estimated the spin of a black hole, this means they have measured its angular momentum. This is the total angular momentum of all the materials on the Universe that ever crossed the event horizon and got trapped inside it.
Therefore, the correct option is C.
Learn more about Angular momentum here:
https://brainly.com/question/29563080
#SPJ2
Suppose you were able to take measurements of current through the
resistor and voltage across the resistor. Your record of numerical values is written in a
tabular data below
Answer:
see attached
Explanation:
It will be easier to plot the data if you have grid lines to work with.
In the attached, we had to reverse the order of entries in the table, because the graphing program likes the independent variable listed first.
5. An acrobat, starting from rest, swings freely on a trapeze of
length 3.7 m (Figure 6). If the initial angle of the trapeze is
48°, use the law of conservation of energy to determine
(a) the acrobat's speed at the bottom of the swing
(b) the maximum height, relative to the initial position, to
which the acrobat can rise
The energy conservation and trigonometry we can find the results for the questions about the movement of the acrobat are;
a) The maximum speed is v = 4.89 m / s
b) The maximum height is h = 1.22 m
The energy conservation is one of the most fundamental principles of physics, stable that if there are no friction forces the mechanistic energy remains constant. Mechanical energy is the sum of the kinetic energy plus the potential energies.
Em = K + U
Let's write the energy in two points.
Starting point. Highest part of the oscillation
Em₀ = U = m g h
Final point. Lower part of the movement
[tex]Em_f[/tex] = K = ½ m v²
Energy is conserved.
Emo = [tex]Em_f[/tex]
m g h = ½ m v²
v² = 2 gh
Let's use trigonometry to find the height, see attached.
h = L - L cos θ
h = L (1- cos θ)
They indicate that the initial angle is tea = 48º and the length is L = 3.7 m, let's calculate.
h = 3.7 (1- cos 48)
h = 1.22 m
this is the maximum height of the movement.
Let's calculate the velocity.
[tex]v= \sqrt{2 \ 9.8 \ 1.22}[/tex]
v = 4.89 m / s
In conclusion using the conservation of energy and trigonometry we can find the results for the questions about the movement of the acrobat are;
a) The maximum speed is v = 4.89 m / s
b) The maximum height is h = 1.22 m
Learn more here: brainly.com/question/13010190
What is the disappearance of a wave into a medium.
A. Signal
B. Amplitude
C. Absorption
D. Transmission
Answer:
Absorption
Explanation:
the disappearance of an EM wave into the medium. scattering – the spreading out of light rays in all directions because particles reflect and absorb the light.
How long would it take a 500 w electric motor to do 150,000 j of work
Explanation:
300 second = 5 minutes
details
500 watts = 500 joules per second
Time = (1.50 x 10^5 joules)/(5 x 10^2 joules per second) = .3 x 10^3 seconds =300 second
How far can a mother push a 20.0 kg baby carriage, using a force of 62 N, if she can only do 2920 J of work?
Please find attached photograph for your answer.
Hope it helps.
One thing I have to mention is that here we do not need to calculate the mass because the amount of force is already given.
Please do comment if you have any query.
Jade has a refractive index of 1.61. If light approaches the gem at an angle of 80.0°, what is the angle of refraction?
Calculate the index of refraction of a material if the angle of incidence is 60° and the angle of refraction is 50°
Answer using calculations & full work and thoughts shown.
From Snell's law, the angle of refraction is 38 degree approximately and the index of refraction is 1.13
The given refractive index is 1.61
If light approaches the gem at an angle of 80.0°, that means the angle of incidence is 80.0°
To calculate the angle of refraction, we will use Snell's law which state that:
n = sin i / sin r
where n = refractive index
Substitute all the parameters into the formula
1.61 = sin 80 / sin r
make sin r the subject of formula
sin r = sin 80 / 1.61
sin r = 0.611
r = [tex]Sin^{-1}[/tex](0.611)
r = 37.7
r = 38 degree (Approximately)
We will use the same formula to calculate the index of refraction of a material if the angle of incidence is 60° and the angle of refraction is 50°. That is,
n = sin i / sin R
Where n = index of refraction
i = Incidence
R = refraction
Substitute all the parameters to the formula
n = sin 60 / sin 50
n = 0.866 / 0.766
n = 1.13
Learn more here: https://brainly.com/question/24321580
What is a net force on an object that has a mass of 20.0 kg, an applied force of 100 n moving on a surface with a friction coefficient of 0.21?
The net force on the object as described is; 58.84N
Two forces acting on the object are;
The applied force and the frictional force.In essence; the frictional force can be evaluated as;
Frictional force; = coefficient × Weight of object.Frictional force = 0.21 × 20 × 9.8.Frictional force = 41.16NThe Net force = Applied force - frictional forceNet force = 100 - 41.16NNet Force = 58.84 N.
Read more:
https://brainly.com/question/94428
a ball is thrown vertically up ward with a velocity of 25m/s. a/how fast was it moving after 2sec?
Answer:
12.5
Explanation:
given
distance=25
time=2sec
required
=speed
solution
=v=s/t
25/2
=12.5m/s