Answer:
The speed of the student just before she lands, v₂ is approximately 8.225 m/s
Explanation:
The given parameters are;
The mass of the physic student, m = 43.0 kg
The height at which the student is standing, h = 12.0 m
The radius of the wheel, r = 0.300 m
The moment of inertia of the wheel, I = 9.60 kg·m²
The initial potential energy of the female student, P.E.₁ = m·g·h₁
Where;
m = 43.0 kg
g = The acceleration due to gravity ≈ 9.81 m/s²
h = 12.0 h
∴ P.E.₁ = 43 kg × 9.81 m/s² × 12.0 m = 5061.96 J
The kinetic rotational energy of the wheel and kinetic energy of the student supporting herself from the rope she grabs and steps off the roof, K₁, is given as follows;
[tex]K_1 = \dfrac{1}{2} \cdot m \cdot v_{1}^2+\dfrac{1}{2} \cdot I \cdot \omega_{1}^2[/tex]
The initial kinetic energy, 1/2·m·v₁² and the initial kinetic rotational energy, 1/2·m·ω₁² are 0
∴ K₁ = 0 + 0 = 0
The final potential energy of the student when lands. P.E.₂ = m·g·h₂ = 0
Where;
h₂ = 0 m
The final kinetic energy, K₂, of the wheel and student is give as follows;
[tex]K_2 = \dfrac{1}{2} \cdot m \cdot v_{2}^2+\dfrac{1}{2} \cdot I \cdot \omega_{2}^2[/tex]
Where;
v₂ = The speed of the student just before she lands
ω₂ = The angular velocity of the wheel just before she lands
By the conservation of energy, we have;
P.E.₁ + K₁ = P.E.₂ + K₂
∴ m·g·h₁ + [tex]\dfrac{1}{2} \cdot m \cdot v_{1}^2+\dfrac{1}{2} \cdot I \cdot \omega_{1}^2[/tex] = m·g·h₂ + [tex]\dfrac{1}{2} \cdot m \cdot v_{2}^2+\dfrac{1}{2} \cdot I \cdot \omega_{2}^2[/tex]
Where;
ω₂ = v₂/r
∴ 5061.96 J + 0 = 0 + [tex]\dfrac{1}{2} \times 43.0 \, kg \times v_{2}^2+\dfrac{1}{2} \times 9.60 \, kg\cdot m^2 \cdot \left (\dfrac{v_2}{0.300 \, m} }\right ) ^2[/tex]
5,061.96 J = 21.5 kg × v₂² + 53.[tex]\overline 3[/tex] kg × v₂² = 21.5 kg × v₂² + 160/3 kg × v₂²
v₂² = 5,061.96 J/(21.5 kg + 160/3 kg) ≈ 67.643118 m²/s²
v₂ ≈ √(67.643118 m²/s²) ≈ 8.22454363 m/s
The speed of the student just before she lands, v₂ ≈ 8.225 m/s.
A rock has a density of 2 g/mL and a mass of 17.5 g. What is the volume of the rock?
HELP PLEASE
Which applications, either for diagnostic purposes or for therapeutic purposes, do not involve ionizing radiation? Check all that apply.
Answer: I do not know (is this an RP question? ;-;)
Explanation:
Answer:
Applications in which ionizing radiation are not used are
MRI
ultrasound
laser surgery
Explanation:
hope its right
bestfriend
An aluminum rod is 300m and at 25 degree Celsius. Calculate the change in rod
length at 45 degree Celsius
Answer:
Explanation:
540
An object is located 20.0 cm from a convex lens. The lens focuses light at a
distance of 10.0 cm. What is the image distance?
A. 6.67 cm
B. -6.67 cm
C. -20.0 cm
D. 20.0 cm
The Answer Is : D. 20.0 cm
My Reason : These types of problems can all be solved using the lens or mirror equation.
1/20 +1/q= 1/10
q=20 cm
The image is formed behind the lens at 2f or the center of curvature.
It is real, inverted, and the same size as the object
The Answer Is: D. 20.0 cm
Explanation: I did the test :)
Two students noted that the acceleration of a car was - 40 km/s^2. The first student said, “That can’t be right. You can’t have a negative acceleration.” The second student said, “That can’t be right. You can’t have s^2.” What would you say to each student to help them better understand how acceleration is described? pls answer
State two advantages of thermal expansion
Higher Power Efficiency and Eliminates Risk of Compressor Breakdown
A 15.0 cm object is 12.0 cm from a convex mirror that has a focal length of -6.0 cm. What is the height of the image produced by the mirror?
–5.0 cm
7.5 cm
-7.5 cm
5.0 cm
Answer:
-7.5
Explanation:
edge 2021
A globe (model of the Earth) is a hollow sphere with a radius of 16 cm. By wrapping a cord around the equator of a globe and pulling on it, a person exerts a torque on the globe of 120 N • m for 1.2 s. What angular momentum does the globe have after 1.2 s?
Answer:
144 kg m^2/s
Explanation:
When two chemical atoms form a chemical bond, the expected result is that the electrons
A.)will be in the excited state
B.) will be equal to the number of protons
C.) will complete a noble gas configuration in both atoms
D.) will be removed completely from both atoms
Answer:
B
Explanation:
atoms with equal or similar electronegativity form covalent bonds in which the valence electrons are shared between the two atom
During the formation of a chemical bond, the expected result is that the electrons will complete a noble gas configuration in both atoms. Hence, option (C) is correct.
The given problem is based on the concepts and fundamentals of chemical bonds. The chemical bonds between the two atomic species is formed by sharing the electrons.
When the electrons from each of the atom is shared, they maintain a strong intermolecular bond, which is known as chemical bond. This chemical bond allows the element to achieve noble gas configuration.The electrons that is shared within the two atomic species are known as shared pairs.The shared pairs are bonded within the atomic species by means of Van der Waals force of attraction as as covalent interaction..Thus, we can conclude that during the formation of a chemical bond, the expected result is that the electrons will complete a noble gas configuration in both atoms. Hence, option (C) is correct.
Learn more about the chemical bonds here:
https://brainly.com/question/23882847
In space, there is no friction. Without the force of friction, satellites and other moving objects will continue moving at the same speed unless they are acted on by other forces.
Which of Newton’s laws of motion best matches this example?
Answer:
Newton's first law
Explanation:
it says that an object will continue to be at rest or keep moving till any external for is applied to it to make it move or stop respectively.
A toy radio-controlled car races around a circular track in a time of 2 MINUTES, with a speed of 5.25 m/s. What is the radius of the
circular track? (will give brainliest)
Answer:
The radius will be "100.31 m". A further solving is given below.
Explanation:
The given values are:
Time,
T = 2 minutes
i.e.,
= 120 seconds
Speed,
V = 5.25 m/s
As we know
⇒ [tex]T=\frac{2 \pi R}{V}[/tex]
then,
⇒ [tex]R=\frac{TV}{2 \pi}[/tex]
On substituting the given values, we get
⇒ [tex]=\frac{120\times 5.25}{2\times 3.14}[/tex]
⇒ [tex]=\frac{630}{6.28}[/tex]
⇒ [tex]=100.31 \ m[/tex]
Which of the following is the best example of motion?
A. Waving your arms
B. Tossing and turning in your bed
C. Walking from home to school
D. Your dog wagging his tail
Answer:
Maybe A. waving your arms?
1.Wave motion that is parallel to the wave direction is described
as_____________ wave.
2. The time to make one complete cycle is _____________.
3. The distance between successive crests of a wave is __________.
4. Wave motion that is perpendicular to wave direction describes a
_____________ wave.
5. The number of waves that passes a given point in time is__________.
6. ____________ is a kind of wave that does not need a medium.
7. The highest point of a wave is called ___________.
8. The unit for frequency is ____________.
9. The part of a longitudinal wave where there are fewer particles is
called______________.
10. A region in a medium of longitudinal wave where molecules are
packed is called _____________.
Answer:
Explanation:
A wave is a phenomenon that travels through a material medium without any permanent effect on the medium. It can be classified as mechanical or electromagnetic waves. And the two major types are transverse and longitudinal.
From the given question;
1. Longitudinal waves e.g sound waves, waves in a spring'
2. Frequency (number of cycles per second).
3. Wavelength of the wave. Measured in meters.
4. Transverse waves e.g light waves, water waves.
5. Wave speed.
6. Electromagnetic waves e.g ultraviolet waves, X-rays etc.
7. Amplitude.
8. Hertz.
9. Rarefaction
10. Compression
A wave is a phenomena that flows across a material medium without leaving any lasting mark.
1.Wave motion that is parallel to the wave direction is described
as longitudinal wave.
What is wave?A wave is a phenomena that flows across a material medium without leaving any lasting mark. Mechanical or electromagnetic waves can be used to classify it. Transverse and longitudinal are the two main forms.
1.Wave motion that is parallel to the wave direction is described
as longitudinal wave.
2.Frequency is defined as the number of cycles per second.. The time to make one complete cycle is frequency.
3.Wavelength of the wave is measured in meters.The distance between successive crests of a wave is wavelength.
4. Examples of Transverse waves are light waves, water waves.. Wave motion that is perpendicular to wave direction describes transverse wave.
5.The number of waves that passes a given point in time is Wave speed.
6.Examples of Electromagnetic waves are ultraviolet waves, X-rays etc.
Electroimegnetic wave is a kind of wave that does not need a medium.
7.The highest point of a wave is called amplitude.
8.The unit for frequency is Hertz.
9. A region in a medium of longitudinal wave where molecules are Rarefaction.
10. A region in a medium of longitudinal wave where molecules are
packed is called compression.
To learn more about the wave refer to the link;
https://brainly.com/question/3004869
What must happen to light in order for an image to form
When 525 J of heat is added to 7.6 g of metal at 26°C, the temperature increases to 80°C. What is the specific heat of the metal?
Ans the answer is 0.25J
Explanation
i guess
______________ controls the flow of electric current.
Answer!!!
Please
Answer:
Explanation:
Its resistor
The National Aeronautics and Space Administration (NASA) studies the physiological effects of large accelerations on astronauts. Some of these studies use a machine known as a centrifuge. This machine consists of a long arm, to one end of which is attached a chamber in which the astronaut sits. The other end of the arm is connected to an axis about which the arm and chamber can be rotated. The astronaut moves on a circular path, much like a model airplane flying in a circle on a guideline. The chamber is located 20.0 m from the center of the circle. At what speed must the chamber move so that an astronaut is subjected to 5.64 times the acceleration due to gravity
Answer:
w = 1,662 rad / s, v = 33.25 m / s
Explanation:
This this exercise indicates that the acceleration felt by the astronauts is
a = 5.64 g
in a circular motion the centripetal acceleration is
a_c = v²/ r
angular and linear variables are related
v = w r
we substitute
a_c = w² r
we finally have
5.64 g = w² r
w² = 5.64 g / r
let's calculate
w = [tex]\sqrt{ \frac{5.64 \ 9.8}{20.0} }[/tex]
w = 1,662 rad / s
linear velocity is
v = w r
v = 1,662 20
v = 33.25 m / s
Bob and Sarah build an electromagnet by wrapping a wire around a nail and connecting the wire to both terminals of a battery. When they test the electromagnet, it can pick up six paper clips. Their teacher wants all groups to pick up at least 10 paper clips. What revisions could Bob and Sarah make to increase the number of paper clips their electromagnet picks up
1). Wrap more turns of the wire around the nail.
2). Increase the electrical current through the wire. (Do this by inserting another battery in the circuit, in series with the first one.)
Use the image to answer Questions 4–6.
What takes place at Point A?
conduction
convection
radiation
sublimation
What takes place at Point B?
conduction
convection
radiation
sublimation
Image attached
Answer:
the first one is c and the second is b
In the early universe and now, stars most likely formed from which of the following?
Group of answer choices
Nebulas
Planets
Comets
Asteroids
Answer:
Nebulas
Explanation:
Nebulae are made of dust and gases—mostly hydrogen and helium. ... Eventually, the clump of dust and gas gets so big that it collapses from its own gravity. The collapse causes the material at the center of the cloud to heat up-and this hot core is the beginning of a star.
What is the momentum of a 200 kg truck travelling at 20 m/s?
Answer:
p = 4000 kg-m/s
Explanation:
Given that,
The mass of a truck, m = 200 kg
Speed of the truck, v = 20 m/s
We need to find the momentum of the truck. The formula for momentum is given by :
p = mv
so,
[tex]p=200\times 20\\\\p=4000\ kg-m/s[/tex]
So, the momentum of the truck is equal to 4000 kg-m/s.
When electrons are moving it is called
A field
B electricity
C friction
D attraction
What will be the final velocity of a rock if we drop it off of a bridge and it strikes the ground 2.8s later (ignoring air resistance)?
GIVING BRAINLIEST PLEASE HELP!!
-if you answer correctly ill give you brainliest which will give you 23pts-
Answer:
B is the answer!!
Explanation:
1. Rearrange the equation for the area of a rectangle (A = l w) to solve for length, l.
Step 1
Step 2
Step 3
Step 4
2. Rearrange the equation for velocity v = d/t to solve for time, t.
Step 1
Step 2
Step 3
Step 4
which best illustrates the relationships between a producer and a consumer
Two balls are rolling using the same force. Which law explains why the bowling ball will roll a shorter distance than a soccer ball ?
1. Newton's 1st law
2. Newton's 2nd law
3. Newton's 3rd law
Answer:
newton's 2nd law
Explanation:
In the first law, an object will not change its motion unless a force acts on it. In the second law, the force on an object is equal to its mass times its acceleration. In the third law, when two objects interact, they apply forces to each other of equal magnitude and opposite direction.
A car increases from 15 km/s to 45 km/s in 5 seconds. Calculate the average acceleration of the car during these 5 seconds. (2 points) A. 6 km/s2 B. 12 km/s2 C. 30 km/s2 D. 60 km/s2
Would Lincoln, Nebraska or San Diego, California have a smaller range in average monthly temperatures
Answer: San diego
Because it is closer to the ocean
Derived and define the units