B
Explanation:
BECAUSE IT WAS GOING UPWORD THEN IT'S VELOCITY WAS DECREASING -10MS¹
Answer:
Explanation:
From physics, which is directly related to math (especially when it comes to parabolic motion!), we learn that at the very top of the parabola the object has to stop for a millisecond so it can turn around and fall back to earth. This translates to a velocity of 0 at its highest point. So B.
Two children (each having a mass of 60 kg) are standing on the edge a merry-go-round (mass of 140 kg) as it spins with an angular velocity of 0.75 rad/s. The two children jump off the merry-go-round. What is the angular velocity of the merry-go-round after the children have jumped off
Answer:
The angular velocity after the children jump off is approximately 1.4 rad/s
Explanation:
The given parameters are;
The masses of each child, m₁, and m₂ = 60 kg
The mass of the merry-go-round, m₃ = 140 kg
The initial angular velocity, [tex]\omega_i[/tex] = 0.75 rad/s
The angular velocity after the children jump off = [tex]\omega_f[/tex]
According to the principle of conservation of angular momentum
The angular momentum = I × ω
The moment of inertia, I = m × R²
The total initial angular momentum = [tex]I_i \times \omega_i = m_i \times R^2 \times \omega_i[/tex]
The total angular momentum after the children jump off = [tex]I_f \times \omega_f = m_f \times R^2 \times \omega_f[/tex]
The initial mass, [tex]m_i[/tex] = m₁ + m₂ + m₃ = 60 kg + 60 kg + 140 kg = 260 kg
The final mass, [tex]m_f[/tex] = m₃ = 140 kg
According to the principle of conservation of linear momentum, we have;
[tex]I_i \times \omega_i[/tex] = [tex]I_f \times \omega_f[/tex]
Therefore;
260 kg × R² × 0.75 rad/s = 140 kg × R² × [tex]\omega_f[/tex]
∴ [tex]\omega _f[/tex] = (260 kg × R² × 0.75 rad/s)/(140 kg × R²) = 1.39285714 rad/s. ≈ 1.4 rad/s
The angular velocity after the children jump off, [tex]\omega _f[/tex] ≈ 1.4 rad/s.
If if two non zero vectors are acted on a body in what condition the resultant vector on the body will be zero ?
Answer:
Yes, when the 2 vectors are same in magnitude and direction. Yes, when the 2 vectors are same in magnitude but opposite in sense. Yes, when the 2 vectors are same in magnitude making an angle of 2π3 with each other.
Explanation:
Hope it helps you
The condition under which the resultant of two vectors will be zero is that the vectors must be in equilibrium.
The conditions under which the resultant of two non zero vectors acting on a body must be zero.
the two vectors must be in equilibriumthe two vectors are forces, then they must lie on the same plane and their line of action must pass through a common point.[tex]\bar R = \bar R_A + \bar R_B = 0[/tex]
Thus, the condition under which the resultant of two vectors will be zero is that the vectors must be in equilibrium.
Learn more here: https://brainly.com/question/17574217
can anyone help me with this one
Answer:
c) sin c /sin d
because light is moving from denser to shallower medium
b) refraction of light
Explanation:
The velocity ratio of a pulley system is 4. What does it means
Answer:
Velocity ratio = distance travelled by effort / distance travelled by load. Which is equal to effort arm / load arm. When velocity ratio (VR) is 4, the effort arm is greater than load arm.
Using your Periodic Table, which of the elements below is most likely to be a solid at room temperature?
A.) potassium, B.) Hydrogen, C.) Neon, D.) Chlorine
The answer is definitely Potassium
25 POINTS 25 POINTS 25 POINTS 25 POINTS 25 POINTS
Assignment: Build an Electromagnet and a Motor Investigation
Electromagnet
1. How many paper clips did the wire wrapped around the nail just a few times pick up?
2. Which electromagnet design was most successful in picking up the most paper clips?
3. Would wrapping the wire more times around the nail make the electromagnet stronger or weaker?
4. What do you think the result would be if an iron nail that was much thicker was used?
5. What do you think would happen if a wooden stick was chosen as the core instead of the iron nail?
Motor
1. Describe the components that are necessary to make a motor run? What do they each provide? (example: battery provides voltage source)
2. Describe how the homemade motor makes mechanical energy from electrical energy.
3. What are three appliances in your house that use a motor that turns electrical energy into mechanical energy?
All the paper clips, coiled wire with nail and wrapping or coiling the wire more times are the correct answers.
All the paper clips will the wire wrapped around the nail just a few times pick up. A coiled wire with nail in the center is the electromagnet design which is most successful in picking up the most paper clips. Wrapping or coiling the wire more times around the nail make the electromagnet more stronger.
If an iron nail that was much thicker was used, it will make the magnet stronger that leads to strong electromagnetism. There are three main parts that is necessary for making a motor i.e. a rotor, a stator and a commutator.
These three parts use the attractive and repulsive forces of electromagnetism, causing the motor to spin continually as long as it receives a steady flow of electric current. Motors comprise of loops of wire in a magnetic field.
When current is passed through the loops, the magnetic field exerts a torque on the loops, which rotates the shaft that leads to the generation of electricity. Water pump, mixer and washing machine are three appliances in your house that use a motor that turns electrical energy into mechanical energy.
https://brainly.com/question/24278437
J.J. Thomson theorized that, if an atom had all of its negatively charged
electrons removed, the remaining material would be
A. neutral
B. negatively charged
C. positively charged
D. magnetic
Answer:
C. Positively charged
Explanation:
The plum pudding model of the atom proposes by J. J. Thomson consisted of electrons which lay embedded as the raisins within a dough or soup that was positively charged. The electron was discovered by J. J. Thomson in 1897 through cathode ray tube experiments.
Based on the plum pudding model, if all the negatively charge electrons contained in an atom are removed, the material remaining will be the positively charged soup
Two manned satellites approach one another at a relative velocity of v=0.190 m/s, intending to dock. The first has a mass of m1=4.00×103 kg and the second a mass of m2=7.50×103 kg. If the two satellites collide elastically rather than dock, what is their final relative velocity?
Answer:
Their final relative velocity is 0.190 m/s
Explanation:
The relative velocity of the satellites, v = 0.190 m/s
The mass of the first satellite, m₁ = 4.00 × 10³ kg
The mass of the second satellite, m₂ = 7.50 × 10³ kg
Given that the satellites have elastic collision, we have;
[tex]v_2 = \dfrac{2 \cdot m_1}{m_1 + m_2} \cdot u_1 - \dfrac{m_1 - m_2}{m_1 + m_2} \cdot u_2[/tex]
[tex]v_2 = \dfrac{ m_1 - m_2}{m_1 + m_2} \cdot u_1 + \dfrac{2 \cdot m_2}{m_1 + m_2} \cdot u_2[/tex]
Given that the initial velocities are equal in magnitude, we have;
u₁ = u₂ = v/2
u₁ = u₂ = 0.190 m/s/2 = 0.095 m/s
v₁ and v₂ = The final velocities of the satellites
We get;
[tex]v_1 = \dfrac{2 \times 4.0 \times 10^3}{4.0 \times 10^3 + 7.50 \times 10^3} \times 0.095 - \dfrac{4.0 \times 10^3- 7.50\times 10^3}{4.0 \times 10^3+ 7.50\times 10^3} \times 0.095 = 0.095[/tex]
[tex]v_2 = \dfrac{ 4.0 \times 10^3 - 7.50\times 10^3}{4.0 \times 10^3 + 7.50 \times 10^3} \times 0.095 + \dfrac{2 \times 7.50\times 10^3}{4.0 \times 10^3+ 7.50\times 10^3} \times 0.095 = 0.095[/tex]
The final relative velocity of the satellite, [tex]v_f[/tex] = v₁ + v₂
∴ [tex]v_f[/tex] = 0.095 + 0.095 = 0.190
The final relative velocity of the satellite, [tex]v_f[/tex] = 0.190 m/s
What is concave mirror?
Answer:
A concave mirror, or converging mirror, has a reflecting surface that is recessed inward (away from the incident light). Concave mirrors reflect light inward to one focal point. They are used to focus light.
Can I answer my own question
Answer:
Well okay do it what's your question ?
Answer:
yes
Explanation:
Pls help me solve these two questions!!! Tq
Answer:
Part A would be 80 Joules and Part B would be 20 meters.
Explanation:
For Part A:
The first step is to convert the mass to SI units.
400 g = 0.4 kg
Next, we need to know that the law of conservation of energy states that the total energy of an isolated system is conserved. In this case, it means that the total energy at the bottom, where kinetic energy is greatest, will be equal to the total energy at the top, where gravitational potential energy is greatest.
Max Gravitational Potential Energy = Max Kinetic Energy
Max Gravitational Potential Energy = [tex]\frac{1}{2} mv^{2}[/tex]
Max Gravitational Potential Energy = [tex](\frac{1}{2} )(.4kg)(20m/s)^2[/tex] = 80[tex]J[/tex]
For Part B:
We need to once again set gravitational potential energy to kinetic energy, only this time we use the GPE equation and solve for height. We already solved for the kinetic energy so we just plug everything in and solve.
[tex]mgh = \frac{1}{2} mv^{2}[/tex]
[tex](.4kg)(10m/s^{2} )h = 80J\\h = 20m[/tex]
Vector A has magnitude of 8units and makes an angle of 45° with the positive x-axis. Vector B also has the same magnitude of 8units and directed along the negative x-axis. Find a. The magnitude and direction of A+B b. The magnitude and direction of A-B
Answer:
Explanation:
Because vectors have direction and x and y components you can't just add them and say that their length is 16 because A is 8 units and so is B. What you're actually finding is the magnitude and direction of the vector that results from this addition. The magnitude is the length of the resultant vector, which comes from the x and y components of A and B, and the direction is the angle between the resultant vector and the positive x axis. To add the vectors, then, we need to find the x and y components of each. We'll do the x components of A and B first so we can add them to get the x component of C. Since x values are directly related to cos, the formula to find the x components of vectors is
[tex]V_x=Vcos\theta[/tex] which is the magnitude of the vector (its length) and the angle. Finding the x components of A:
[tex]A_x=8.0cos45[/tex] so
[tex]A_x=5.7[/tex] and for B:
[tex]B_x=8.0cos180[/tex] since the negative x axis is the 180 degree axis and
[tex]B_x=-8.0[/tex] If we add them, we get
[tex]C_x=-2.3[/tex]
Now onto the y components. The formula for that is almost the same as the x components except use sin instead of cos:
[tex]A_y=8.0sin45[/tex] so
[tex]A_y=5.7[/tex] and
[tex]B_y=8.0sin180[/tex] so
[tex]B_y=0[/tex] If we add them, we get
[tex]C_y=5.7[/tex]
Now for the final magnitude:
[tex]C_{mag}=\sqrt{(-2.3)^2+(5.7)^2}[/tex] and
[tex]C_{mag}=6.1 units[/tex] and now onto the direction.
The x component of C is positive and the y component is negative, which means that the direction has us at an angle is quadrant 2; we add 180 to whatever the angle is. Finding the angle:
[tex]tan^{-1}(\frac{C_y}{C_x})=(\frac{5.7}{-2.3})[/tex] = -68 + 180 = 112 degrees
The resultant vector of A + B has a magnitude of 6.1 and a direction of 112°
Do the same thing for subtraction, except if you're subtracting B from A, the direction that B is pointing has to go the opposite way. That means that A doesn't change anything at all, but B is now pointing towards 0.
[tex]A_x=5.7[/tex] (doesn't change from above)
[tex]B_x=8.0cos0[/tex] and
[tex]B_x=8.0[/tex] so
[tex]C_x=13.7[/tex] and
[tex]A_y=5.7[/tex] (also doesn't change from above)
[tex]B_y=8.0sin0[/tex] so
[tex]B_y=0[/tex] and
[tex]C_y=5.7[/tex] and for the magnitude:
[tex]C_{mag}=\sqrt{(13.7)^2+(5.7)^2[/tex] so
[tex]C_{mag}=15units[/tex] and for the direction:
[tex]tan^{-1}(\frac{5.7}{13.7})=23[/tex] and since both x and y components of C are in Q1, we add nothing.
And you're done!!!
A comet of mass 2 × 10^8 kg is pulled toward the star. If the comet's initial velocity is very small, and the comet starts moving toward the star from 700,000,000 km away, how fast is it going right before it hits the surface of the star? (Assume that it does not lose any mass by melting as it approaches the star.)
Answer:
The speed of the comet at the surface of the star is approximately 1,208,694.7 m/s
Explanation:
Question parameter obtained online; The mass of the star, M = 5 × 10³¹ kg
Explanation;
The given mass of the comet, m = 2 × 10⁸ kg
The initial velocity of the comet, v → 0
The distance of the comet from the star, d = 700,000,000 km
The gravitational potential at d = G·M·m/d
The kinetic energy of the comet, K.E. = m·v²/2
The kinetic energy of the comet at d = m·(0)²/2 = 0
The gravitational potential at the surface of the star, R = G·M·m/R
The kinetic energy of the comet at the surface of the star, R = m·(v)²/2 = 0
Where;
M = The mass of the star = 5 × 10³¹ kg
[tex]M_{Sun}[/tex] = The mass of the Sun = 1.989 × 10³⁰ kg
M/[tex]M_{Sun}[/tex] = 5 × 10³¹/(1.989 × 10³⁰) ≈ 25
G = The universal gravitational constant = 6.67430 × 10⁻¹¹ N·m²/kg²
R = The radius of the star
Therefore, we have;
m·(0)²/2 - G·M·m/d = m·v²/2 - G·M·m/R
∴ v = √((G·M·m/R - G·M·m/d)×2/m) = √(2·G·M(1/R - 1/d))
Therefore; v = (2 × 6.67430 × 10⁻¹¹ × 5 × 10³¹ × (1/R - 1/700,000,000,000))
v = 81696389149.1×√(1/R - 1/700,000,000,000).
The speed of the comet at the surface of the star, v = 81696389149.1×√(1/R - 1/700,000,000,000)
The mass radius relationship is given as follows;
[tex]\dfrac{R}{R_{Sun}} = 1.30 \times \left(\dfrac{M}{M_{Sun}} \right)^{\dfrac{1}{2} }[/tex]
[tex]R = R_{Sun} \times 1.30 \times \left(\dfrac{M}{M_{Sun}} \right)^{\dfrac{1}{2} }[/tex]
The radius of the Sun = 696,340,000 M
∴ R ≈ 696,340,000 × 1.3 × √(25.14) = 4538865694.76
R = 4538865694.76 m
v = 81696389149.1×√(1/4538865694.76 - 1/700,000,000,000) ≈ 1208694.7 m/s
Multi-part question If a galaxy moving away from the Earth has a speed of 1000 km/s and emits 656 nm light characteristic of hydrogen (the most common element in the universe). What wavelength would we observe on the Earth
Answer:
658.2 nm
Explanation:
Since the galaxy is moving at relavitistic speed, we use the equation for relativistic Doppler shift of light.
So, the wavelength of light observed on the Earth is λ
λ = λ'([tex]\sqrt{\frac{ 1 + \frac{v}{c} }{1 - \frac{v}{c} } }[/tex])
where λ' = wavelength of light emitted by galaxy = 656 nm, v = speed of galaxy = 1000 km/s (positive since the galaxy is moving away from the Earth) and c = speed of light = 300000 km/s
So, substituting the values of the variables into the equation, we have
λ = λ'(√[{1 + (v/c)}/(1 - (v/c)]
λ = 656 nm(√[{1 + (1000 km/s/300000 km/s)}/(1 - (1000 km/s/300000 km/s)]
λ = 656 nm(√[{1 + 1/300}/(1 - 1/300]
λ = 656 nm(√[{(300 + 1)/300}/{(300 - 1)/300}]
λ = 656 nm(√[{(301)/300}/{(299)/300}]
λ = 656 nm(√[301/299])
λ = 656 nm(√1.0067)
λ = 656 nm × 1.0033
λ = 658.19 nm
λ ≅ 658.2 nm
So, the wavelength observed on Earth is 658.2 nm
Q010) A well in which the water rises on its own to a level above its aquifer Group of answer choices is the result of pressure within a confined aquifer that creates a potentiometric surface. is called an ordinary well. always pushes water higher than the ground surface. cannot be used for commercial or public use, as the water is under too much pressure.
Answer:
The result of pressure within a confined aquifer that creates a potentiometric surface
Explanation:
There are conditions under the Earth's surface, where porous rock layers are tilted and also have a confining, less porous, rock layer about the their boundary, forming a confined aquifer. The existing pressure in the aquifer is therefore confined within the water and the porous rock layer, such that drilling into the pressurized aquifer leads to the water rising under the pressure existing in the aquifer, to a potentiometric surface which is above the actual underground level of the aquifer
solve two questions under inclined plane using Newton 2nd law
Explanation:
If the mass of the inclined plane is large enough, could N ever be equal to mgcosθ. Reasons?
So far I've come up with: mgcosθ−N=ma meaning if N were to equal mgcosθ, ma=0. Since the surfaces are frictionless and since N is acting on the inclined plane too(it'll have a horizontal component), this isn't possible. Am I right? Where am I going wrong?
state one similarity and one difference of sound of frequency 750Hz and ultrasound
Explanation:
Ultrasound refers to sound waves having frequencies greater than the frequency range limit. Ultrasound has the same physical qualities as "regular" (audible) music, except that individuals cannot hear it. Ultrasound devices use frequencies ranging from 20 kHz to a few gigahertz.
The frequencies of ultrasound utilised in clinical settings are generally between 2 and 12 MHz. Shorter wavelengths have a larger penetration depth into the body but less resolution; longer wavelengths have a greater depth of penetration but have a restricted depth of penetration.
You are pushing a cart at the grocery store. The cart is speeding up. a) When your friend drops a 50 pound bag of dog food into the cart you are pushing, what would happen to the acceleration of the cart? Explain your answer using Newton's Second Law.
Answer:
The acceleration will decrease/reduce
Explanation:
Newton in his second law of motion states that the acceleration of an object is dependent on the force and mass applied on the object. Using the equation as follows:
F = m × a
Where;
F = force (N)
m = mass (kg)
a = acceleration (m/s²)
Acceleration (a) is directly proportional to the force (F) applied but inversely proportional to the mass (m).
According to this question, a friend drops 50 pounds of dog food into a cart being pushed with speed. This means that the mass/weight of the cart was increased. Since the acceleration is inversely proportional to the mass of an object, this means that the acceleration of the cart will DECREASE/REDUCE as the mass increases.
En un rio una Onda viaja con una velocidad de propagación de 50 m/s con una longitud de Onda de 40 metros. Hallar la frecuencia de la Onda.
Answer:
Frequencia = 1.25 Hz
Explanation:
Dados los siguientes datos;
Velocidad = 50 m/s Longitud de onda = 40 metrosPara encontrar la frecuencia de la onda;
Matemáticamente, la velocidad de una onda viene dada por la fórmula;
[tex] Velocidad = Longitud \; de \; onda * Frequencia [/tex]
Haciendo de la frecuencia el tema de la fórmula, tenemos;
[tex] Frequencia = \frac {Velocidad}{Longitud \; de \; onda} [/tex]
Sustituyendo en la fórmula, tenemos;
[tex] Frequencia = \frac {50}{40} [/tex]
Frequencia = 1.25 Hz
Joule is equal to:
Awatt x metre
B.watt x second
C. Newton x Metre
D. Both b and c
Answer:
The answer is ( D) i. e both b and c.
You're driving down the highway late one night at 20 m/s when a deer steps onto the road 35 m in front of you. You reaction time before stepping on the brakes is 0.50 s, and the maximum deceleration of your car is 10 \mathrm { m } / \mathrm { s } ^ { 2 }10m/s 2 . a. How much distance is between you and the deer when you come to a stop
Answer:
Explanation:
Discount the time here; it's not important. It doesn't tell you how long it takes the car to stop, it only refers to reaction time, which means nothing in the scheme of things.
The useful info is as follows:
initial velocity = 20 m/s
final velocity = 0 m/s
a = -10 m/s/s
and we are looking for the displacement. Use the following equation:
[tex]v^2=v_0^2+2a[/tex]Δx
where v is the final velocity, v₀ is the initial velocity, a is the deceleration (since it's negative), and Δx is displacement. Filling in:
[tex]0^2=(20)^2+2(-10)[/tex]Δx and
0 = 400 - 20Δx and
-400 = -20Δx so
Δ = 20 meters
Which of the following is occurring while a satellite is in orbit around Earth? O It is continuously pulling away from Earth It is continuously falling toward the surface of Earth. It stays in a constant speed orbit where it was oriented from the start. It stays in the same orbit orientation traveling at variable speeds.
AnswerIt is continuously falling towards the surface of the earth
Explanation:
since gravity from earth is the thing that keeps it constantly in orbit
why does the satellite not fall while revolving the earth
Answer:
Satellites don't fall from the sky because they are orbiting Earth. Even when satellites are thousands of miles away, Earth's gravity still tugs on them. Gravity--combined with the satellite's momentum from its launch into space--cause the satellite go into orbit above Earth, instead of falling back down to the ground.
state and prove Newton's second law of motion
Answer:
HOPE IT HELP YOU A LOT :)
I prove it also .
Answer:
Newtons Second law of motion states that"The rate of change of momentum is directly proportional to the force applied"
Please help! Will mark Brainliest
Explanation:
I think it is the third image as marked in the diagram I kept above because as we know first class levers have the fulcrum between the force and the load
Để có 100 lít nước ở 370C. Người ta pha nước đang sôi với nước ở 150C. Tính thể tích nước mỗi loại cần dùng.Biết khối lượng riêng của nước là 1000kg/m3
Answer:
nước sôi: 440/17 l
nước 15°C:1260/17 l
Why does the Earth exert a gravitational force on objects on its surface?
A. It has an atmosphere,
B. It has mass
C. It has a magnetic field.
D. It is so dense.
Answer:
B. It has mass
Explanation:
The Newtons Universal gravitacion law is : F = G.[tex]\frac{m1 m2}{d^{2} }[/tex] , where F is the force exerted , m1 and m2 are the earth's mass and the object's mass, d is the distance and G the gravitacional constant. Comparing to the options we can say that the Earth exerts a gravitational force on objects on its surface because of its mass.
difference Between Newton's first and third 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.6 days ago
Newton first law state that anything in motion or on rest will continue to do so until an external force is applied on it
Newton 3rd law stare that every action have equal and opposite reaction
standard unit definition
Answer:
Standard units are the units we usually use to measure the weight, length or capacity of objects.
Answer:
THE SYSTEM OF UNITS WHICH IS AGREED BY THE INTERNATIONAL CONVENTION OF SCIENTISTS HELD IN FRANCE IN 1960 IS CALLED SI SYSTEM.
Q: Riri wants to bake a cake. She adds flour, sugar, egg, baking soda, and yeast into a bowl and mixed them together. After all the ingredients are mixed, she leaves the dough for 30 minutes and the dough starts to rise. Which changes Occurred in this process? Explain your reason.
Answer:
I don't know what you mean about which changes occurred in this process but if its why the dough starts rising then its caused by the carbon dioxide in baking soda and yeast which is a fungus
Answer:
When baking,flour is mixed with water,the other ingredients and yeast to form a paste called a dough.what happens is that the zymase enzyme from the yeast acts on the sugars to form carbon dioxide and alcohol.the carbon dioxide begins to form bubbles in the dough causing it to rise..
I hope this helps
