Answer:
the answer is b
Explanation:
Answer:
b
Explanation:
1.- Un balín de acero a 20 C tiene un volumen de 0.004 m3. ¿Cuál es la dilatación que sufre cuando su temperatura aumenta a 50 C?
Answer:
[tex]\Delta V = 1.440\times 10^{-6}\,m^{3}[/tex]
Explanation:
El coeficiente de expansión volumétrica se calcula a partir de la siguiente ecuación diferencial parcial (The volumetric expansion coefficient is computed by means of the following partial differential equation):
[tex]\alpha = \frac{1}{V} \cdot \left(\frac{\partial V}{\partial T} \right)[/tex]
Se integra la fórmula a continuación (The formula is integrated herein):
[tex]\alpha\, dT = \frac{dV}{V}[/tex]
Supóngase que el coeficiente es constante (Let suppose that coefficient is constant):
[tex]\alpha \int\limits^{T_{f}}_{T_{o}}\,dT = \int\limits^{V_{f}}_{V_{o}}\, \frac{dV}{V}[/tex]
[tex]\alpha \cdot (T_{f}-T_{o}) = \ln \frac{V_{f}}{V_{o}}[/tex]
El volumen final es (The final volume is):
[tex]V_{f} = V_{o}\cdot e^{\alpha \cdot (T_{f}-T_{o})}[/tex]
El coeficiente de expansión volumétrica del acero es [tex]12\times 10^{-6}\,^{\circ}C^{-1}[/tex] (The volumetric expansion coefficient of steel is [tex]12\times 10^{-6}\,^{\circ}C^{-1}[/tex]):
[tex]V_{f} = (0.004\,m^{3})\cdot e^{(12\times 10^{-6}\,^{\circ}C^{-1})\cdot (50^{\circ}C-20^{\circ}C)}[/tex]
[tex]V_{f} \approx 4.001\times 10^{-3}\,m^{3}[/tex]
Finalmente, la dilatación experimentada por el balín es (Lastly, the dillatation experimented by the pellet is):
[tex]\Delta V = 4.001\times 10^{-3}\,m^{3} - 4.000\times 10^{-3}\,m^{3}[/tex]
[tex]\Delta V = 1.440\times 10^{-6}\,m^{3}[/tex]
La dilatación que sufre un balín de acero al pasar de 20 C a 50 C es de 0.00000432 m^3. Esta respuesta se obtiene aplicando la formula de dilatación volumétrica y asumiendo el coeficiente de dilatación volumétrica para el acero es de aproximadamente 0.000036 1/C.
El problema nos pide encontrar la dilatación del acero cuando su temperatura sube de 20 C a 50 C. La dilatación es un fenómeno físico donde los objetos cambian de tamaño debido a los cambios de temperatura. Para entender esto mejor, supongamos que es necesario calcular la dilatación volumétrica de un objeto hecho de acero cuando su temperatura cambia.
La fórmula general para el cálculo de la dilatación volumétrica es: ΔV = β·V0·ΔT, donde ΔV es la dilatación, β es el coeficiente de dilatación volumétrica (acero tiene un valor de aproximadamente 0.000036 1/C), V0 es el volumen inicial ( en este caso 0.004 m3) y ΔT es el cambio de temperatura en grados Celsius (50 C - 20 C = 30 C).
Entonces, sustituimos los valores en la fórmula: ΔV = 0.000036 1/C * 0.004 m3 * 30 C = 0.00000432 m3
Por lo tanto, cuando la temperatura del balín de acero aumenta de 20 C a 50 C, sufre una dilatación de 0.00000432 m3.
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If 270 watts of power is used in 42 seconds, how much work is done? (Unit is joules (J), just type the number. Use commas if necessary).
Answer:
11340
Explanation:
Power = Work/time.
P = W/t ................ Equation 1
Make W the subject of the equation,
W = Pt.................. Equation 2
Given: P = 270 Watts, t = 42 seconds
Substitute these values into equation 2
W = 270(42)
W = 11340 J
Hence the work done is 11340
Answer:11340 J
Explanation:
A cell phone weighing 80 grams is flying through the air at 15 m/s. What’s is it’s kinetic energy
Answer:
The kinetic energy of the cell phone is 9J
Explanation:
The kinetic energy is the energy possessed by a body by virtue of motion.
The kinetic energy is expressed as
KE= 1/2m(v)²
Given data
Mass of cell phone m= 80g--to kg=80/1000= 0.08kg
Velocity of cell phone v= 15m/s
Substituting our given data we have
KE= 1/2*0.08(15)²
KE= (0.08*225)/2
KE=18/2
KE= 9J
Before coming to school, Angela used electrical energy to warm her breakfast, light up a room, and charge her cell phone. Which statement about electrical energy is true? * 1 point If the charged particles are moving, electrical energy is a type of kinetic energy. If uncharged particles are moving, electrical energy is a type of potential energy. If the charged particles are not moving, electrical energy is a type of kinetic energy. If the charged particles are moving, electrical energy is a type of potential energy.
Answer:
If the charged particles are moving, electrical energy is a type of kinetic energy
Explanation:
This is because the electrical energy converted to kinetic energy of the charges. If q is the magnitude of the charge and V the electric potential it passes through, if it has a mass, m, it will develop a speed, v due to kinetic energy given by
qV = 1/2mv²
v = √(2qV/m)
A sample of a radioactive elements must contain atoms
A.
with a stable nuclei
B.
with unstable nuclei
C.
in the excited state
D.
in the ground state
A radioactive element's sample must contain atoms with unstable nuclei, which undergo radioactive decay to achieve stability.
A sample of a radioactive element must contain atoms with unstable nuclei. Radioactive elements consist of isotopes whose nuclei have an imbalance in the number of protons and neutrons leading to an unstable configuration. This causes these nuclei to spontaneously emit particles or radiation in a process known as radioactive decay. During radioactive decay, an unstable isotope changes into a more stable isotope, often of a different element. Radioactive elements must contain atoms with unstable nuclei. These nuclei undergo radioactive decay, emitting particles to become a different nucleus. A nucleus with too few or too many neutrons will tend to undergo radioactive decay to achieve greater stability. Elements with atomic numbers above 92 are all synthetically produced and do not occur naturally on Earth—they are examples of artificial radioactivity.
Ariana is accelerating her car at a rate of 4.6 m/s2 for 10 seconds. Her starting velocity was 0 m/s.
What was her final velocity?
0 m/s
2.3 m/s
4.6 m/s
46 m/s
The final velocity of the car is 46 m/s
Data obtained from the question Acceleration (a) = 4.6 m/s²Time (t) = 10 sInitial velocity (u) = 0 m/sFinal velocity (v) =?How to determine the final velocity
The final velocity of the car can be obtained as follow:
v = u + at
v = 0 + (4.6 × 10)
v = 0 + 46
v = 46 m/s
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What concept or principle best explains why
the cab of a truck is often separated from the
load by a steel barrier?
load
a. acceleration
b. the force of friction
e. the normal force
d. Newton's first law
Answer:
d. Newton's first law
I hope this helps you
The steel barrier in a truck acts as a protective measure due to Newton's first law of motion, or the law of inertia, which states that objects in motion tend to stay in motion unless acted upon by an unbalanced force.
The concept or principle that best explains why the cab of a truck is often separated from the load by a steel barrier is Newton's first law of motion. This law, also known as the law of inertia, states that an object at rest stays at rest, and an object in motion remains in motion with the same speed and in the same direction unless acted upon by an unbalanced force. In the case of a truck, if it were to suddenly stop or be involved in a collision, the load would tend to continue moving due to inertia. The steel barrier is there to prevent the load from entering the cab and possibly harming the occupants.
Inertia is a fundamental aspect of Newton's first law, indicating the resistance of any physical object to a change in its state of motion. The barrier serves as a safety feature to protect against the dangers posed by inertia; without it, any objects in the load could cause injury to those in the cab during a sudden stop or crash due to their tendency to keep moving forward.
Scientists around the world have been working for decades on perfecting the process of
nuclear fusion in the lab. Which statement justifies this research?
Answer:
Scientists are looking for a way to create cheap, safe, and sustainable energy.
Nuclear fusion is the process by which two atoms rapidly collide at each other forming a new nucleus. The energy of colliding and synthesizing has intrigued scientist into believing that this could be one of best sources of renewable energy.Explanation:
Answer:
d
Explanation:
e2020
Which event occurs after erosion of earth's surface
Answer:
Surface material breaks down into smaller pieces
Explanation:
The event that occurs after erosion is that very dense particles settle faster than low-density particles.
The term erosion refers to the washing away of top soil. Erosion may be caused by;
WindWaterIn both cases, land is rendered unfit for agricultural purposes hence every method must be employed to avoid erosion.
The event that occurs after erosion is that very dense particles settle faster than low-density particles.
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how is acceleration related to force when mass is constant , according to Newton’s second law of motion
Final answer:
Acceleration is directly proportional to force when mass is constant, according to Newton's second law of motion, which can be represented by the formula F = ma.
Explanation:
According to Newton's second law of motion, when the mass is constant, acceleration is directly proportional to the force applied to a system. In simpler terms, if you apply more force to an object of constant mass, its acceleration will increase. Conversely, if you apply less force, the acceleration decreases. Newton's second law can be expressed with the formula F = ma, where F stands for force, m for mass, and a for acceleration.
This relationship implies that for a given mass, the acceleration is always in the same direction as the force applied. If you push an object forward, it will accelerate forward. When the mass of the system does not change, the equation simplifies the understanding of how force affects the system's motion. The constant mass ensures that any change in force results in a proportional change in acceleration.
В каких из перечисленных случаев тело приобретает потенциальную энергию? А) воду в реке поднимают с помощью плотины В) пуля вылетает из ружья С) недеформированную пружину сжимают D) на земле лежит камень
Answer: D) a stone lies on the ground
Explanation:
Potential energy this is defined as the mechanical energy, energy stored, or energy created by the position of an object. Example; energy possessed by a ball while hanging at the top of a steep hill when about to roll down is called a potential energy. This is same as a stone which lies in a floor.
The _____ law of thermodynamics states that two objects in thermal equilibrium will have no net heat flow between them. zeroth first second
Answer:
THE ZEROETH LAW
Explanation:
IM JUST TO SMART FOR THIS SHIIIIIIIII
Answer:
ZEROTH
Explanation:
odyssey
Which best describes the energy of a sound wave as it travels through a medium?
The correct option is d) it decreases. A sound wave transfers energy through a medium by particle vibrations, creating compressions and rarefactions that propagate as longitudinal waves.
A sound wave transfers energy through the medium primarily by the vibrations of the particles in that medium. This propagation occurs as a longitudinal wave, which means the particle displacements are parallel to the direction of the wave's travel. The speed at which sound travels depends on the medium's rigidity (or compressibility in gases) and its density. Sound waves travel faster in more rigid or less dense materials and slower in less rigid or denser materials.
Key Points About Sound Waves:
Energy Transfer: Sound waves transfer energy through particle vibrations in the medium.
Wave Propagation: Sound waves are longitudinal waves.Affecting Factors: Medium's rigidity and density affect the speed of sound. Option d.Question:
Which best describes the energy of a sound wave as it travels through a medium?
a. it remains the same
b. It increases.
c. It depends on the medium
d. it decreases.
Technician a says that using a pressure transducer and lab scope is a similar process to using a vacuum gauge. technician b says the pressure transducer may be used to tie any issues to individual cylinders if paired with a second trace consisting of the ignition pattern. who is correct?
Answer: Both Technician A and B
Explanation:
There is a similar process in using a pressure transducer and lab scope to using a vacuum gauge.
And also, the pressure transducer can be used to tie any issues to individual cylinders if paired with a second trace consisting of the ignition pattern. Therefore, both Technician A and B are correct.
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which point has the most PE?
which point has the most KE?
which point has the most TE?
Does the skier lose or gain thermal energy as she skies down the slope? how do you know?
Question 1. A satellite’s velocity is 30,000m/s. After 60 seconds, it’s velocity slows to 15,000 m/s. What is the satellite’s acceleration?
Question 2. A speed boat increases its speed from 42 m/s to 88m/s in a 4 second period. What is the acceleration during this period?
Explanation:
1.
Initial speed of satellite is 30,000 m/s
Final speed of satellite is 15000 m/s
Time taken by the satellite to reach final speed is 60 s
The satellite’s acceleration is equal to the change in velocity divided by time taken. So,
[tex]a=\dfrac{v-u}{t}\\\\a=\dfrac{15000 -30000}{60}\\\\a=-250\ m/s^2[/tex]
2.
Initial speed of a boat is 42 m/s
Final speed of a boat is 88 m/s
Time taken is 4 s
The acceleration of boat during this period is :
[tex]a=\dfrac{v-u}{t}\\\\a=\dfrac{88-42}{4}\\\\a=11.5\ m/s^2[/tex]
x=3t^2-12t+5 calculate time t=1 and time when velocity zero
The element Ne, neon, has ____ (number) complete shells having its ____ electrons in second _____.
What are the answers to the blanks?
Answer:
2, 8 and shell
Explanation:
Neon as atomic number 10. Since for each shell, electrons equal 2n².
When n = 1, 2n² = 2(1)² = 2
When n = 2, 2n² = 2(2)² = 8
So it fills both the first and second shell with 2 and 8 electrons respectively to achieve its stable atomic state. The rest of the 8 electrons go into the second shell because the first shell has achieved its stable dual configuration of two electrons. The next shell requires a maximum of 8 electrons to achieve stability so, the remaining electrons fill it up to achieve the stable octet configuration.
An athlete completes one round of a circular track of diameter 200 m in 40 s. What will be the distance covered and the displacement at the end of 2 minutes 20 s?
Answer:
Explanation:
Displacement is the shortest distance possible between initial and final position.
As the athlete is in circular motion , displacement is zero. [ THis is because , the initial and final position is the same ]
Distance covered in 1 round = Circumference of the circle
Circumference of the circle = 2πr
Diameter = 200 m
Radius = 100 m
Distance covered in 1 round[ 40 sec ] = 2 × 22/7 × 100 = 628.57 m
Distance covered in 1 sec = 628.57 ÷ 40 = 15.71 m
2min 20 sec = 140 sec
Distance covered in 140 sec = 15.71 × 140 = 2199.4 m
For each complete round the displacement is zero. Therefore for 3 complete rounds, the displacement will be zero.
At the end of his motion, the athlete will be in the diametrically opposite position. That is, displacement = diameter = 200 m.
Hence, the distance covered is 2200 m and the displacement is 200 m.
The voltage in a circuit can be determined from the ____, total resistance, and capacitance
The voltage in a circuit can be determined from the current, total resistance, and capacitance. The correct option is D.
What is current?The current is the stream of charges flowing from the positive terminal of the voltage source to the its negative terminal.
A simple circuit consists of a voltage source or battery and resistance, current will flow when connected. But, if circuit has capacitance and resistance, the current will flow from the circuit.
Thus, the voltage in a circuit can be determined from the current, total resistance, and capacitance. The correct option is D.
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How do you determine the acceleration of an object?
Question options:
Subtract the starting velocity from the ending velocity
Determine the average velocity and divide by the distance traveled
Multiply the change in velocity by the time interval
Divide the change in velocity by the time interval
Divide the change in velocity by the time interval
For the acceleration of an object, divide the change in velocity by the time interval.
To calculate an object's acceleration, divide the change in velocity by the time period. The right answer is: Divide the velocity change by the time period.
The rate at which an object's velocity varies over time is measured as acceleration. It is computed by dividing the velocity change by the time it takes for that change to occur. The acceleration formula is:
Acceleration = (Change in Velocity) / (Time Interval)
Thus, by determining the change in velocity (the difference between the final velocity and the initial velocity) and dividing it by the time interval, you can find the object's acceleration.
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Psi communication refers to the transfer of information through a/an ________ process.
Answer:
unknown
Explanation:
Psi communication: The term "Psi communication" was initially originated in an article named 'Mass Communication and Para-Social Interaction' during 1956 by Donald Horton, and is also denoted as "parasocial interaction". It is described as a phenomenon that involves "one-sided interaction" between people, encompassing the viewer knowing a specific celebrity well whereas the viewer himself or herself is being completely unknown for the celebrity in return.
In the question above, the given statement represents that the Psi communication is responsible for transforming via an unknown process as one of its members are considered as unknown of the transfer, so the correct answer would be "unknown process".
how is buoyancy used in the real world?
Answer:
to mack boats float
Explanation:
without it the boats will sink to the bottom
-- Buoyancy is used to bring crude oil from Saudi Arabi to refineries in the US. The oil is loaded into tanks that are part of supertanker ships. Buoyancy is created by their ship-shape, so they float on water, and they can be dragged across the ocean on top of the water.
-- Buoyancy is used for a cheap thrill on the weekend. People drive out in the country and find a place where they can buy a ride under a hot-air balloon. The balloon is filled with hot air from a propane burner under its opening, and then it rises up off the ground because of its buoyancy in cool air.
-- Buoyancy is used cleverly by factories, to get rid of their gaseous and particulate wastes. The wastes are heated, and then blown into tall "smokestacks" connected to the factory. Then they rise because of the buoyancy created by hot stuff in cool air. When they leave the top of the smokestack, they keep rising for a while. Then, weather systems blow them away from the factory, over into other people's neighborhoods, where they finally sink to the ground in places where nobody knows where they came from.
-- Buoyancy is used in teapots, coffee makers, and lava lamps. A heat source is placed under the bottom of the container. Heat is conducted through the bottom of the container, and it heats the fluid that's in contact with the inside of the container on the bottom. The hot fluid rises to the top of the container, because of the buoyancy created by hot stuff surrounded by cool stuff. At the same time, cool stuff flows in to take its place at the bottom.
In pots and pans and tanks where buoyancy is used this way, the motion of the fluids up and down and around is called "convection".
The period of an ocean wave is 5 seconds. What is the wave's frequency?
Answer:
Frequency is the reciprocal of the period. The period is 5 seconds, so the frequency is 1/(5 s) = 0.20 Hz.
Explanation: yes
You wish to lift a 400 lb car engine a vertical distance of 3 ft using a strong rope. Unfortunately, your hand crank winch can only generate 100 lb of tension in your rope. In order to overcome this obstacle, you use a multiple pulley system (block and tackle) to lift the engine.
a)What is the mechanical advantage of this system?
b) What length of rope is required to complete the work?
Answer:
a) 4b) 12ftExplanation:
a) Mechanical Advantage is defined as the ratio of the load to the effort applied to an object. Mechanical advantage occurs when we can use a minimal effort to overcome a much larger load.
Mathematically; Mechanical advantage = Load/ Effort
Load = 400 lb car engine
Effort applied = Tension generated by the hand crank in the rope = 100lb
Mechanical Advantage = 400lb/100lb
MA = 4
b) Assuming the efficiency is 100%
Efficiency = Workdone by the machine/Work put in the machine * 100%
Workdone by the machine = work output = Force * distance moved by load
= 400*3
= 1200lbft
Work put in the machine = Work input = Force * distance moved by effort
Work input = 100*d
substituting into the equation;
100% = 1200/100d * 100%
1 = 1200/100d
100d = 1200
d = 1200/100
d = 12ft
The length of the rope required to complete the work is 12ft
Explain how refraction and prisms work.
Final answer:
Refraction is the bending of light as it passes from one medium to another, and it is pronounced in a prism, where light is separated into its constituent colors through dispersion. Prisms utilize the law of refraction to create a spectrum of colors, as each color is refracted differently based on its wavelength.
Explanation:
Refraction occurs when light enters a new transparent medium and is bent either towards or away from the line perpendicular to the boundary surface. This bending is due to a change in the speed of light as it moves from one medium to another, such as from air into glass. When light passes through a prism, a triangular piece of glass with refracting surfaces, this effect is seen clearly.
The separation of light into different colors is termed dispersion, and it happens because not all colors are bent by the same amount. The deviation of each beam of light depends on its wavelength and the properties of the refracting material. In a prism, violet light is bent more than red light, resulting in the formation of a rainbow spectrum.
The law of refraction, or Snell's law, explains the change in direction of the light rays when they enter a medium with a different index of refraction. According to Huygens's principle, each point of a wavefront acts as a new source of wavelets, which spread out in the second medium at a slower speed, thus bending the wavefront. Prisms use this principle to not only divert but also break up light into its constituent colors, leading to the beautiful dispersion effect observed.
What is a characteristic of a base?
increases amount of hydrogen ions
turns litmus paper red
is slippery
tastes sour
Answer: Bases are slippery.
Explanation:
Bases and acids can be determined by the amount of hydrogen or hydroxide ions in each solution. If a solution has more hydrogen ions than hydroxide ions, it is acidic, whereas if it has more hydroxide ions than hydrogen ions, it is basic.
Using a litmus paper test for a acidic/basic solution, the paper will turn different colors. In an acidic solution, paper will turn red, but in a basic solution, paper will turn blue.
Bases, compared to acids, feel slippery on the skin because they interact with fatty acids on the skin. Comparatively, acids feel sticky.
Acids taste sour. Think of an acid like lemon juice, compared to bases, which taste bitter (blood, for example)
Answer:
What is a characteristic of a base? Is slippery
Explanation:
Have a great day.
A thin, uniform, metal bar, 3 m long and weighing 90 N , is hanging vertically from the ceiling by a frictionless pivot. Suddenly it is struck 1.6 m below the ceiling by a small 4-kg ball, initially traveling horizontally at 12 m/s . The ball rebounds in the opposite direction with a speed of 5 m/s. Find the angular speed of the bar just after the collision? Why linear momentum not conserved?
Angular speed after collision: approximately 0.285 rad/s. Linear momentum not conserved due to external force.
To find the angular speed of the bar just after the collision, we can use the principle of conservation of angular momentum.
Before the collision, the system (bar + ball) has zero angular momentum because both the bar and the ball are stationary relative to the pivot point.
After the collision, the angular momentum of the system is conserved. We can write:
[tex]\(I_1\omega_1 + mvr = I_2\omega_2\)[/tex]
where:
[tex]- \(I_1\) is the moment of inertia of the bar about the pivot point before the collision,[/tex]
[tex]- \(I_2\) is the moment of inertia of the bar about the pivot point after the collision,[/tex]
[tex]- \(\omega_1\) is the initial angular speed of the bar,[/tex]
[tex]- \(\omega_2\) is the final angular speed of the bar,[/tex]
[tex]- \(m\) is the mass of the ball,[/tex]
[tex]- \(v\) is the velocity of the ball, and[/tex]
[tex]- \(r\) is the distance from the pivot point to the point where the ball strikes the bar.[/tex]
Given that the bar is hanging vertically, its moment of inertia about the pivot point is [tex]\(I = \frac{1}{3}ml^2\), where \(m\) is the mass of the bar and \(l\)[/tex] is its length. Substituting the given values:
[tex]\(I_1 = \frac{1}{3}(90\, \text{N})(3\, \text{m})^2 = 270\, \text{kg m}^2\)[/tex]
The moment of inertia of the bar does not change after the collision because no external torque is applied. So [tex]\(I_1 = I_2\).[/tex]
The distance from the pivot point to the point where the ball strikes the bar is [tex]\(r = 1.6\, \text{m}\).[/tex]
Substituting the values into the conservation of angular momentum equation:
[tex]\(270\omega_1 + (4\, \text{kg})(12\, \text{m/s})(1.6\, \text{m}) = 270\omega_2\)[/tex]
Solving for [tex]\(\omega_2\):[/tex]
[tex]\(270\omega_1 + 76.8 = 270\omega_2\)[/tex]
Now, we need to find [tex]\(\omega_1\). Since the bar is initially at rest, \(\omega_1 = 0\).[/tex]
[tex]\(0 + 76.8 = 270\omega_2\)[/tex]
[tex]\(\omega_2 = \frac{76.8}{270} \, \text{rad/s} \approx 0.285\, \text{rad/s}\)[/tex]
So, the angular speed of the bar just after the collision is approximately [tex]\(0.285\, \text{rad/s}\).[/tex]
As for why linear momentum is not conserved, it's because an external force (the impact of the ball) is acting on the system. Linear momentum is only conserved in a system where there are no external forces acting on it. In this case, the collision between the ball and the bar introduces an external force, causing linear momentum not to be conserved.
The angular speed of the bar just after the collision is approximately 3.94 rad/s. Linear momentum is not conserved in this situation due to external forces acting on the system, such as gravity and the pivot support force. Angular momentum is conserved because these external forces don't exert torques around the pivot point.
To solve this problem, we need to consider the conservation of angular momentum. we first evaluate the change in angular momentum of the ball. Then, we find the moment of inertia (I') of the pivot. since the principle of conservation of angular momentum states that the change in angular momentum of the ball is equal to the angular momentum of the bar, we can use this to calculate the angular speed of the bar.
The ball strikes the bar at a point 1.6 m below the ceiling, so the distance from the pivot point is 1.6 m.
The initial angular momentum of the ball: L₁ = m₁ × v₁ × r = 4 kg × 12 m/s × 1.6 m = 76.8 kg·m²/s
The final angular momentum of the ball: L₂ = m₁ × v₂ × r = 4 kg × (-5 m/s) × 1.6 m = -32 kg·m²/s
Net change in angular momentum of the ball: ΔL = L₁ - L₂ = 76.8 kg·m²/s - (-32 kg·m²/s) = 108.8 kg·m²/s
The moment of inertia of the bar about the pivot is: I' = (1/3) × M × L² = (1/3) × (90 N / 9.8 m/s²) × (3 m)² ≅ 27.6 kg·m²
Using conservation of angular momentum:
ΔL = I' × ω' where ω' = angular speed of the bar
⇒ 108.8 kg·m²/s = 27.6 kg·m² × ω'
Therefore, the angular speed of the bar, ω' ≅ 3.94 rad/s
The reason why angular momentum is not conserved is because there are external forces (such as gravity and the pivot support force) acting on the system. These forces exert impulses during the collision, affecting the linear momentum but not the angular momentum.
a rollercoaster goes down hill
a. kinetic energy is converted into potential energy
b. potential energy is converted into kinetic energy
c. electrical energy is converted into potential energy
d. potential energy is converted into electrical energy
Answer:
a. potential energy is converted into kinetic energy
Explanation:
potential energy is the energy something has when it isn't in motion, as the roller coaster goes down hill (moves) the potential energy is turned into kinetic energy
What electromagnetic waves are used in transmitting data from remote controls to televisions?
Radio Waves
Microwaves
Infrared Waves
X-ray
Answer:
Radio waves
Explanation:
Radio waves have the lowest frequency and are the least harmful to humans and animals so they are used in tv remotes, cell phones and anything that transmits data.
Answer:
It's infrared waves
Explanation: