Answer:
v = 14.7m/s
Explanation:
When the rock was at the top of cliff it had only Potential Energy and no Kinetic Energy but soon as the rock hit the ground all the Potential Energy converted into Kinetic Energy so by the Law of Conservation of Energy
[tex]Potential\ Energy = Kinetic\ Energy\\mgh=\frac{1}{2}mv^2\\\\v^2=\frac{2mgh}{m} \\\\v^2=2gh[/tex]
because all of that potential energy got converted into kinetic energy so we use the following formula as we need to calculate the velocity (v)
[tex]Potential\ Energy = Kinetic\ Energy\\mgh=\frac{1}{2}mv^2\\\\v^2=\frac{2mgh}{m} \\\\v^2=2gh[/tex]
here we know [tex]g = 9.8m/s^2[/tex] because the rock was under free fall motion so it had acceleration of 9.8 but we do not the height which is h but we do know the formula:
[tex]Velocity=\frac{Displacement}{Time}[/tex]
the height h is the displacement so we replace height with the following:
[tex]Velocity=\frac{Displacement}{Time}\\\\Displacement=Velocity*Time\\h=vt[/tex]
now, insert h = vt in the above equation
[tex]v^2=2gh\\\\v^2=2g(vt)\\v^2=2vgt\\\\\frac{v^2}{v} =2gt\\\\v=2gt\\v=2(9.8)(0.75)\\v=14.7m/s[/tex]
Kiran's mother placed a candle in the bowl as shown and lit it . A little while later , kiran opened a bottle of pepsi and poured it quickly into the bowl .What will happen ?
Answer:
The candle stick flame will burn brighter.
Explanation:
I majored in Physics.
Marcie weighs 98 lbs. What is her mass?
Answer:
44.492 kg
Explanation:
Convert pounds to kilograms.
1 lb = 0.454 kg
98 lb * 0.454 kg =44.492 kg
Answer:
what he said above is correct yes
Explanation:
What is a displacement can filled with when used to measure the density of an irregular shape?
Answer:
water, it's usually because it's just the easiest to use, but yeah it's water
Suppose an automobile has 2000-joules of kinetic energy. when it moves at twice the speed, what will be its kinetic energy? what's its kinetic energy at three times the speed?
Answer:
K.Eₓ = 4 K.E
K.Eₓ = 9 K.E
Explanation:
Th formula for the kinetic energy of a body is given as follows:
[tex]K.E = \frac{1}{2}mv^2\\[/tex] ---------------equation (1)
where,
K.E = Kinetic Energy of Automobile
m = mass of automobile
v = speed of automobile
For twice speed:
vₓ = 2v
then,
[tex]K.E_{x} = \frac{1}{2}mv_{x}^2\\K.E_{x} = \frac{1}{2}m(2v)^2\\K.E_{x} = 4\frac{1}{2}mv^2\\[/tex]
using equation (1):
K.Eₓ = 4 K.E
For thrice speed:
vₓ = 3v
then,
[tex]K.E_{x} = \frac{1}{2}mv_{x}^2\\K.E_{x} = \frac{1}{2}m(3v)^2\\K.E_{x} = 9\frac{1}{2}mv^2\\[/tex]
using equation (1):
K.Eₓ = 9 K.E
A. The kinetic energy of automobile when it moves at twice the speed is 8000 J
B. The kinetic energy of automobile when it moves at three times the speed is 18000 J
Let the mass of the automobile be constant.
Let the initial velocity be v
A. Determination of the kinetic energy of the automobile when it moves at twice the speed.
Initial kinetic energy (KE₁) = 2000 JInitial velocity (v₁) = vFinal velocity (v₂) = 2vFinal kinetic energy (KE₂) =?KE₁ /v₁² = KE₂ / v₂²
2000 / v² = KE₂ / (2v)²
2000 / v² = KE₂ / 4v²
Cancel out v²
2000 = KE₂ / 4
Cross multiply
KE₂ = 2000 × 4
KE₂ = 8000 J
B. Determination of the kinetic energy of the automobile when it moves at three times the speed.
Initial kinetic energy (KE₁) = 2000 JInitial velocity (v₁) = vFinal velocity (v₂) = 3vFinal kinetic energy (KE₂) =?KE₁ /v₁² = KE₂ / v₂²
2000 / v² = KE₂ / (3v)²
2000 / v² = KE₂ / 9v²
Cancel out v²
2000 = KE₂ / 9
Cross multiply
KE₂ = 2000 × 9
KE₂ = 18000 J
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does anyone know the answers to these ?
What is the frequency of motion of a 2.0m long pendulum?
A) 0.35 Hz
B) 0.61 Hz
C) 1.3 Hz
D) 2.84 Hz
Answer: it’s c
Explanation:
Given an objects momentum and velocity which equation can be used to calculate the objects mass
In order to have more power you would need to do the same about of work
Answer:
....
Explanation:
Two kids are playing tag. The first kid is running at an unknown speed chasing the other. The first kid has a mass of 25 kg and a KE of 450 J.
How fast is the first kid running?
I really need help
Answer:
1mph
Explanation:
A Object has a constant mass . If the force increases, the acceleration will ...
Answer:
increase
Explanation:
Answer:
Increase
Explanation:
A force that acts on an object causes the object to accelerate.
F=ma
When mass is kept constant, force is directly proportional to the acceleration. Meaning that if the force increases, the acceleration increases, and if force decreases the acceleration decreases.
When force is kept constant, acceleration is inversely proportional to mass.
Meaning that when the mass of the objet increases, the acceleration of the object will decrease, and if the mass of the object decreases, the acceleration will increase.
Hope this helped!
What is the supply voltage?
Answer:
[sə′plī ‚vōl·tij] (electricity) The voltage obtained from a power source for operation of a circuit or device.
Explanation:
hope this helps :)
Perform the following operation observing proper significant digits.
323.7 cm+ 100 cm+ 6.8 cm= _____.
A. 430.51 cm
B. 429.0 cm
C. 430.5 cm
D. 431 cm
Answer:
430.5 cm
Explanation:
first we detect point digt than
323+100+6
=429
now point digt
0.7+0.6
1.5
add both:-
429+1.5
=430.5
PLEASE HELP ;w;
What is the difference in energy expended to do work between a crane lifting a 100-N block 6 m above the ground versus a crane lifting a 100-N block 11 m above the ground?
0 J
5 J
100 J
500 J
Answer:
500 J
Explanation:
100 X 6=600
100 X 11=1,100
1,100-600=500J
What is the spreading out of light into different colors called?
1 transmission
2 dispersion
3 reflection
4 refraction
Answer:
Dispersion
Explanation:
dispersion
[diˈspərZHən, diˈspərSHən]
NOUN
the action or process of distributing things or people over a wide area.
"some seeds rely on birds for dispersion"
the state of being dispersed over a wide area.
"the general dispersion of Hellenistic culture"
ecology
the pattern of distribution of individuals within a habitat.
(Dispersion)
another term for diaspora.
a mixture of one substance dispersed in another medium.
physics
the separation of white light into colors, or the separation of any radiation according to wavelength.
statistics
the extent to which values of a variable differ from a fixed value such as the mean.
https://www.bing.com/search?q=dispersion+definition&cvid=293d01094a47488e8fa9919708bffe09&aqs=edge.2.69i57j0l8.1396j0j1&pglt=169&FORM=ANNTA1&PC=HCTS&adlt=strict&toWww=1&redig=FB19F11E98CD4962B2F34295172E44F7
A bungee jumper hangs from a bungee cord with zero velocity. If the bungee
cord has a spring constant of 18 N/m and the jumper has a mass of 113 kg,
how stretched is the bungee cord past its natural length?
A. 1.56 m
B. 61.5 m
C. 6.27 m
D. 18.2 m
SUBMIT
Answer:
C maybe
Explanation:
A bungee jumper hangs from a bungee cord with zero velocity. If the bungee cord has a spring constant of 18 N/m and the jumper has a mass of 113 kg, he streched 6.27 m.
What is Zero velocity?The zero-velocity surface is a concept that relates to the N-body problem of gravity. It represents a surface a body of given energy cannot cross, since it would have zero velocity on the surface.
It was first introduced by George William Hill. The zero-velocity surface is particularly significant when working with weak gravitational interactions among orbiting bodies.
For the purpose of locating Lagrange points, the zero-velocity surface is another crucial factor. In the rotating coordinate system, these points correspond to places where the apparent potential is extreme.
Therefore, A bungee jumper hangs from a bungee cord with zero velocity. If the bungee cord has a spring constant of 18 N/m and the jumper has a mass of 113 kg, he streched 6.27 m.
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A ski jumper has a mass of 59.6 kg. She is moving with a speed of 23.4 m/s at a height of 44.6 meters above the ground. Determine the total mechanical energy of the ski jumper. Assume negligible air resistance and friction. (3 pts)
Hello!
Use the formula:
M = k * p
Data:
M = Mechanic energy
k = Kinetic energy
p = Potencial energy
Descomposing:
M = (0,5*mv²) + (mgh)
Replacing:
M = (0,5 * 59,6 kg * (23,4 m/s)²) + (59,6 kg * 9,81 m/s² * 44,6 m)
M = 16317,28 J + 26076,54 J
M = 42393,82 J
The mechanic energy is 42393,82 Joules.
4. A car travels 3 km due North, then 5 km East Represent
these displacements graphically and determine the resultar
displacement
Answer:
x^2 =5^2+3^2
25+9
=
[tex] x = \sqrt{34} [/tex]
Answer:
3kmIsquare +5km isquare9km isquare + 25km isquare
34km isquare
if a book of mass 50 kg is placed on the table of mass 200 kg what will be the weight of table and reaction of table on the book?
Answer:
See the answer below.
Explanation:
The weight of the table should be equal to the weight of the table plus the weight of the book.
[tex]w_{table}=m_{table}*g\\w_{table}=200*9.81\\w_{table}=1962[N][/tex]
And for the book
[tex]w_{book}=m_{book}*g\\w_{book}=50*9.81\\w_{book}=490.5[N][/tex]
And the total weight
[tex]w = w_{table}+w_{book}\\w=1962+490.5\\w = 2452.5 [N][/tex]
For the system to be in balance, the reaction force exerted by the table on the book must be equal to the weight of the book. This force in physics is known as the normal force.
[tex]N_{force} = w_{book}\\N_{force}=490.5[N][/tex]
10. A tennis ball rolled off the edge of a table that has a height of 1,00 m.
The ball took 0.45 s to hit the ground 0.72 m from the table. What was the horizontal velocity
of the ball as it rolled off the table?
Answer:
The answer is "[tex]1.6\ \frac{m}{s}[/tex]"
Explanation:
Distance= 0.72 meter
time= 0.45 second
The formula for horizontal velocity:
[tex]horizontal \ velocity = \frac{distance}{time}\\\\[/tex]
[tex]=\frac{0.72}{ 0.45}\\\\= 1.6 \ \frac{m}{s}\\\\[/tex]
If an organism had the following organelles: mitochondria, chloroplast, ribosome, nucleus, cell wall, and cell membrane, what type of organism is the cell found
A. Plant and Animal
B. Only Animal
C. Animal & Fungi
D. Only plants
Answer:
D
Explanation:
One type of potential energy is gravitational potential energy. What is necessary for an object to have gravitational potential energy?
Gravitational potential energy is energy an object possesses because of its position in a gravitational field. The most common use of gravitational potential energy is for an object near the surface of the Earth where the gravitational acceleration can be assumed to be constant at about 9.8 m/s2. Since the zero of gravitational potential energy can be chosen at any point (like the choice of the zero of a coordinate system), the potential energy at a height h above that point is equal to the work which would be required to lift the object to that height with no net change in kinetic energy. Since the force required to lift it is equal to its weight, it follows that the gravitational potential energy is equal to its weight times the height
Gravitational potential energy is the potential energy with respect to the gravitational force. To possess gravitational potential energy, the object to be placed in a position in the gravitational field.
What is potential energy?Potential energy of body is the energy generated by virtue of the position of the body. Whereas kinetic energy is generated by virtue of its movement.
Potential energy and kinetic energy together called as mechanical energy. The potential energy p is mathematically expressed as p = mgh. Where g s gravity, h is height and m is the mass.
The gravitational potential energy is arised in an object due the position in gravitational field. It changes with the change in position and change in height from the ground. A change in mass also alter the gravitational potential energy.
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How is it technically correct to say that a car making a u-turn can have a constant speed but cannot have a constant velocity?
During the "U" part of the turn, the car would follow an approximately circular path, and if it's moving at a constant speed, it would have to accelerate toward the center of the circle in order to change its direction.
28. A student notices that when a weight is hung on a spring, the spring stretches. She decides to conduct an experiment to determine the relationship between the amount of weight
placed on a spring and the distance the spring stretches. She has five different weights: 25 9,50 9, 75 9, 100 g, and 125 g. She selects a weight, hangs it on the spring, and
measures how far the spring stretches
What is the independent variable in this experiment?
length of unstretched spring
O distance the spring stretches
weight hung from the spring
O temperature of the spring
Answer:
weight hung from the spring
Explanation:
An "independent variable" refers to the variable that is being changed or manipulated in an experiment. This is being done in order to check its impact on the "dependent variables." The independent variable does not rely on any other variables.
In the experiment above, the independent variable is the "weight." This variable is being manipulated in order to know how far the spring will stretch. This is the reason why there are five different weights, which means there will be five different distances expected to be covered by the spring.
Two circular rods, both of length L and having the same diameter, are placed end to end between rigid supports with no initial stress in the rods. The coefficient of linear expansion and Young's modulus for rod A are αA and YA respectively; those for rod B are αB and YB respectively. Both rods are "normal" materials with α>0. The temperature of the rods is now raised by ΔT.
What is the stress F/A in the rods after heating?Express the stress in terms of ?A, ?B, YA, YB, and ?T.
Answer:
[tex]\mathbf{\dfrac{F}{A}= -\dfrac{( \alpha_A + \alpha _B)\Delta T}{\bigg ( \dfrac{1}{Y_A}+ \dfrac{1}{Y_B}\bigg )} }[/tex]
Explanation:
From the information given.
The formula for Youngs modulus(Y) can be illustrated as follows:
[tex]Y = \dfrac{F/A}{\Delta L /L}[/tex]
where;
F = force
A = area
ΔL / L = the fraction of the change that occurred in the length.
If we make ΔL / L the subject of the formula, the above expression can be re-written as:
[tex]\dfrac{\Delta L}{L } = \dfrac{1}{Y}\dfrac{F}{A}[/tex]
However, the total fractional change that occurred in the length can be computed as:
[tex]\dfrac{\Delta L_{compressive \ stress}}{L} = \dfrac{\Delta L_A}{L_A} + \dfrac{\Delta {L_B}}{L_B}[/tex]
where;
[tex]L = L_A = L_B[/tex]
The area of both rods is said to be equal as well.
Thus;
[tex]\dfrac{\Delta L_{compressive \ stress}}{L} = \dfrac{1}{Y_1} \dfrac{F}{A}+ \dfrac{1}{Y_2}\dfrac{F}{A}[/tex]
[tex]\dfrac{\Delta L_{compressive \ stress}}{L} =\bigg( \dfrac{1}{Y_1} + \dfrac{1}{Y_2} \bigg ) \dfrac{F}{A}[/tex] ----- Let this be equation (1)
Recall that:
[tex]\dfrac{\Delta L }{L }= \alpha \Delta T[/tex]
in which
ΔL = change in length
L = the original length of rod before extension
∝ = coefficient of linear expansion
ΔT = temperature change
Similarly:
The total fractional change in the length is:
[tex]\Delta L _{thermal} = \Delta L_A +\Delta L_B[/tex]
[tex]\Delta L _{thermal} = \alpha_AL \Delta T+\alpha_BL \Delta T[/tex]
[tex]\dfrac{\Delta L _{thermal}}{L} =( \alpha_A+ \alpha _B) \Delta T \ \ \ ---(2)[/tex]
The sum of both the thermal and compressive stress of the combined rod is equal to the fractional change.
Mathematically:
[tex]\Delta L_{net} = \Delta L_{thermal} + \Delta L_{compressive \ stress}[/tex]
where;
[tex]\Delta L_{net} =0[/tex]
∴
[tex]0 = \Delta L_{thermal} + \Delta L_{compressive \ stress}[/tex]
[tex]\Delta L_{compressive \ stress} =- \Delta L_{thermal}[/tex]
From equation (1) & (2)
[tex]\bigg( \dfrac{1}{Y_1} + \dfrac{1}{Y_2} \bigg ) \dfrac{F}{A}= - (\alpha_A + \alpha_B) \Delta T[/tex]
Making the stress [tex]\dfrac{F}{A}[/tex] the subject, we get;
[tex]\mathbf{\dfrac{F}{A}= -\dfrac{( \alpha_A + \alpha _B)\Delta T}{\bigg ( \dfrac{1}{Y_A}+ \dfrac{1}{Y_B}\bigg )} }[/tex]
is throwing a ball against a wall newton's 3rd law ?
Answer: Yes
Explanation: Yes
1.-Sean los siguientes vectores A=3i + 2j - 7 k B=3J + 6 K + 5 i Hallar a) |A| b) A+B c) |A+B| d) A-B e) 2A+3B
Answer:
A = 2,
Explanation:
(3 + 2) - 7
2 - A: 2
3 + 6 + 5
14 - B: 14
YOUR WELCOME
A tennis ball is hit with a tennis racket. The force of the racket on the ball compared to the force of the ball on the racket is
1- smaller
2- Larger
3- The same
The force of the racket on the ball compared to the force of the ball on the racket is the same. So, option (3) is correct.
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.
Every time one object applies force to another, the other object applies an equal and opposing force to the first.
According to Newton's third law, there is an equal and opposite reaction to every force (action) in nature. When object A pulls on item B, object B pulls back on object A with an equal and opposing force. In other words, interactions lead to forces. So, the force of the racket on the ball compared to the force of the ball on the racket is the same.
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Which of the following can occur when an object is accelerating?
A. It speeds up
B. It slows down
C.
Changes in Direction
D.
All of the above is acceleration
Answer:
D
Explanation:
Change in speed or direction is acceleration
An object accelerates when it is moving faster. Option A is corect.
What is acceleration?The rate of velocity change concerning time is known as acceleration. According to Newton's second law, the eventual effect of all forces applied to a body is its acceleration.
The pace at which a body's velocity varies is represented by acceleration, which is a vector quantity.
[tex]\rm a = \frac{v-u}{t}[/tex]
Where,
u is the initial speed in m/sec
v is the final speed in m/sec
t is the time interval in sec
a is the acceleration in m/sec²
When an object is accelerating it speeds up.
Hence option A is correct.
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HELP ME PLEASE!!!!!! A couch is pushed with a force of 79 N and moves a distance of 7 m across the floor. How much work was done in moving the couch?
HELP ASAP!! WILL TRY TO GIVE BRAINLIEST
How are ribosomes different from other complex animal cell organelles?
