Answer:
Explanation:
This is a First Law of thermodynamics problem. We have to remember that the total energy available to a system is constant throughout the whole problem and that energy cannot be created or destroyed. So we need to find the total energy available right at the start. Well it just so happens that we are told that the total energy is 1000J and that it is all potential energy when the sphere is at rest and is 25 m off the ground. If the object isn't moving, all the energy is potential until it starts moving and the energy begins to convert from potential to kinetic a little bit at a time. The thing that we don't know is the mass of the shpere. Begin with the fact that the PE = 1000 (I'm going to se 2 sig fig's since there's only 1 in 1000). If
PE = 1000 and PE = mgh, then
1000 = m(9.8)(25) so
m = 4.1 kg
We also need the height at which this sphere has a PE of 600. Again, if
PE = 600 and PE = mgh, then
600 = (4.1)(9.8)h so
h = 15 Filling in the total energy equation now, using the fact that the total energy available to the system is 1000J:
TE = PE + KE and
1000 = (4.1)(9.8)(15) + [tex]\frac{1}{2}(4.1)v^2[/tex] and we are looking for v.
1000 = 6.0 × 10² + 2.1v² so
[tex]v=\sqrt{\frac{1000-6.0*10^2}{2.1} }[/tex] and
[tex]v=\sqrt{\frac{4.0*10^2}{2.1} }[/tex] gives us
v = 14 m/s
what is latent heat of vaporization?
The amount of energy required for a unit mass of a substance to undergo a phase change from liquid to gas.
In a cup game if the teams have the same score at the end of the match, 30 minutes of ------- are played.
Answer:
second lag
Explanation:
If in a cup game, a specified time limit is assigned to both teams to score high. If both teams are unable to score or if score of both the teams is equal then there is another second lag played where each team tries to score high. Even if in second lag both teams fail to score higher than other the last third lag is played or else game is declared draw.
Is torque only produced when the force is applied perpendicular to the moment arm?
The Torque is only produced when the force is applied perpendicular to the moment arm.
What is moment of force?The equal and opposite force acting at a point from the axis of rotation is called the moment.
M = F x r
Moment of force is also called as Torque.
Moment arm is the distance of the point of application of force from the axis of rotation of the body.
Thus, the perpendicular component only, produces the torque.
Learn more about moment of force.
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Gas to liquid with explanation on the basis of kinetic model and condensation point.
Answer:
Explanation:
1)Melting:
Melting is the process by which a substance changes from the solid phase to the liquid phase. ... Melting occurs when the internal energy of a solid increases, usually through the application of heat or pressure, such that the molecules become less ordered.
2) liquefication:
In physics and chemistry, the phase transitions from solid and gas to liquid (melting and condensation, respectively) may be referred to as liquefaction. The melting point (sometimes called liquefaction point) is the temperature and pressure at which a solid becomes a liquid.
3) vaporization:
Vaporization, conversion of a substance from the liquid or solid phase into the gaseous (vapour) phase. If conditions allow the formation of vapour bubbles within a liquid, the vaporization process is called boiling. Direct conversion from solid to vapour is called sublimation.
4) Sublimation occurs as molecules of a substance in the solid state go to the vapor state directly, rather than through the liquid state. ... ⭕In terms of the kinetic molecular theory, we know that molecules are in constant random motion, even when the substance is below the melting point.
Sí un auto viaja a 8m/s determine Tiempo en llegar a 200km de distancia Distancia que recorre en 40 minutos
Answer:
a. Tiempo = 25000 segundos
b. Distancia = 19200 metros
Explanation:
Dados los siguientes datos;
Velocidad = 8 m/s
Distancia = 200 km a metros = 200 * 1000 = 200,000
Para encontrar el tiempo para cubrir la distancia anterior;
Tiempo = distancia/velocidad
Tiempo = 200000/8
Tiempo = 25000 segundos
b. Para encontrar la distancia recorrida en 40 minutos;
Tiempo = 40 minutos a segundos = 40 * 60 = 2400 segundos
Distancia = velocidad * tiempo
Distancia = 8 * 2400
Distancia = 19200 metros
Each tire on a car has a radius of 0.330 m and is rotating with an angular speed of 11.7 revolutions/s. Find the linear speed v of the car, assuming that the tires are not slipping against the ground. v
Answer:
The linear speed of the car, v, is 24.26 m/s
Explanation:
Given;
radius of the car's tire, r = 0.330 m
angular speed of the car, ω = 11.7 revolutions/s
The angular speed of the car in radian per second:
[tex]\omega = 11.7 \ \frac{rev}{s} \times \frac{2\pi \ rad}{1 \ rev} \\\\\omega = 73.523 \ rad/s[/tex]
The linear speed of the car, v, is calculated as;
v = ωr
v = 73.523 rad/s x 0.33 m
v = 24.26 m/s
Therefore, the linear speed of the car, v, is 24.26 m/s
A planet has a circular orbit around a star. It is a distance of 53,000,000 km from the centre of the star.
It orbits at an average speed of 49,000 km/h.
How many Earth days does it take the planet to orbit the star?
Give your answer to 2 sf.
Answer:
it takes 365 days to revolve around the star(sun)
what happens to the force when the distance increases between 2 particales
(a) What is the escape speed on a spherical asteroid whose radius is 301 km and whose gravitational acceleration at the surface is 0.412 m/s2
Answer:
[tex]V.E=498.02m/s^2[/tex]
Explanation:
From the question we are told that:
Radius [tex]r=301Km[/tex]
Gravitational acceleration [tex]g=0.412 m/s^2[/tex]
Generally the equation for Escape velocity is mathematically given by
[tex]V.E^2=2gr[/tex]
[tex]V.E^2=2*0.412m/s^2*301000[/tex]
[tex]V.E^2=248024[/tex]
[tex]V.E=\sqrt{248024}[/tex]
[tex]V.E=498.02m/s^2[/tex]
physics class 9 chapter 8 please tell please
Answer:
(a) The motion is uniform
(b) 11.11 m/s
Explanation:
(a)
From the table below, the motion of the bus is uniform.
(b)
Speed(s) = Δd/Δt
s = Δd/Δt............. Equation 1
From the table,
Given: Δd = 10 km = 10000 m, Δt = 15 minutes = (15×60) = 900 seconds
Substitute these values into equation 1
s = 10000/900
s = 11.11 m/s
The atmosphere of Venus is mostly carbon dioxide, and the atmosphere of the Earth has water vapor. Why are these two gases absent in the atmosphere of the satellite around Saturn called Titan
Answer:
if these gases existed in Titan, this n in solid form, by which its absence in the atmosphere is understood.
Explanation:
Each gas and chemical compound has a defined temperature for changes of state, specifically for the change from gaseous to liquid and from liquid to solid state we have
gas gas → liquid liquid → solid
(ºC) (ºC)
H₂0 (Water) 100 0
CO₂ -56.6 (P> = 5.2 bar) <-56.6
The temperature of the Titan satellite is - 180ºC
From the above, if these gases existed in Titan, this n in solid form, by which its absence in the atmosphere is understood.
d. 'g' vanishes at centre of
6) A prism of 6° is made of material of refractive index What is the
deviation caused by it
d. 40
c.120
a. 60
b.8°
7) An object is placed 1cm from lens having magnification 5. Then its foc
length is
a. 0.8 cm b. 1.2 cm c. -1.2 cm d. -0.8cm
Answer:
a. 0.8 cm
Explanation:
The distance of the object from the lens, u = 1 cm
The magnification of the lens, m = 5
The focus of a lens formula is given as follows;
[tex]f = \dfrac{1}{\dfrac{1}{v} + \dfrac{1}{v} }[/tex]
The magnification of the lens, m = -v/u
Where;
v = The distance of the image from the lens
Therefore, we have;
v = m × u
∴ v = 5 × 1 cm = 5 cm (on the other side of the lens)
From which we get;
[tex]f = \dfrac{1}{\dfrac{1}{1} + \dfrac{1}{5} } = \dfrac{5}{6} \approx 0.8[/tex]
The focal length ≈ 0.8 cm
18.How much momentum will a dump-bell of mass 10 kg transfer to the floor if it falls from a height.of 80 cm ? Take its downward acceleration to be 10 m s-2
Such asSuch ToSuch aSuch as طHow do I send the answer to the question?OkI don't know how to use this program
Answer:
MOMENTUM = 40kg ms-¹
hope it helps
have a nice day
As a girl pushes and object across a wood floor she suddenly comes to an area where the floor has been waxed recently making it slippery . What becomes true if the coefficient of kinetic friction
Answer:
This question is incomplete but the completed question is below
As a girl pushes an object across a wood floor, she suddenly comes to an area where the floor has been waxed recently, making it slippery. What becomes true of the coefficient of kinetic friction? A. The coefficient of kinetic friction increases. B. The coefficient of kinetic friction decreases. C. The coefficient of kinetic friction becomes zero. D. The coefficient of kinetic friction becomes negative.
The correct option is B
Explanation:
Coefficient of kinetic friction can be defined as the frictional force resisted by the motion of an object. From the question, it might take the girl to apply a force equivalent to just half that of the weight of the object to overcome friction to keep the object moving on a wood floor. Once she gets to the waxed area, the frictional force reduces, thereby also reducing the coefficient of kinetic friction further. Thus, she will be able to use less than half of the force (equivalent to less than half of the weight of the object) to push the object.
Thus, the correct option is B.
From laboratory measurements, we know that a particular spectral line formed by hydrogen appears at a wavelength of 121.6 nanometers (nm). The spectrum of a particular star shows the same hydrogen line appearing at a wavelength of 121.8 nm. What is the receding speed of the star? c = 3x10^5 km/s
Answer:
[tex]v=-4.93\times 10^{5}~m/s[/tex] [negative sign denotes that it is moving away]
Explanation:
Actual wavelength of hydrogen spectral lines, [tex]\lambda=121.6~nm[/tex]
Apparent wavelength of hydrogen spectral lines from a star, [tex]\lambda'=121.8~nm[/tex]
So, shift in wavelength:
[tex]\Delta \lambda=\lambda'-\lambda[/tex]
[tex]\Delta \lambda=121.8-121.6[/tex]
[tex]\Delta \lambda=0.2~nm[/tex]
Using Doppler's shift:
[tex]\frac{\Delta \lambda}{\lambda} =-\frac{v}{c}[/tex]
[tex]\frac{0.2}{121.6} =-\frac{v}{3\times 10^8}[/tex]
[tex]v=-4.93\times 10^{5}~m/s[/tex] [negative sign denotes that it is moving away]
¿Cuántos electrones por segundo pasan a través de una sección de alambre que lleva una corriente de 0.70 A.?
Answer:
The number of electrons flowing per second is [tex]4.375\times 10^{18}[/tex].
Explanation:
How many electrons per second pass through a section of wire that carries a current of 0.70 A.?
Current, I = 0.7 A
time, t = 1 s
According to the definition of current, let the charge is q.
q = I t
q = 0.7 x 1 = 0.7 C
Let the number of electrons is n.
[tex]n =\frac{q}{e}\\\\n = \frac{0.7}{1.6\times 10^{-19}}\\\\n = 4.375\times 10^{18}[/tex]
A squirrel jumps into the air with a velocity of 4 m/s at an angel of 50 degrees. What is the maximum height reached by the squirrel?
Answer:
Explanation:
Assuming the squirrel is jumping off the ground, here's what we know but don't really know...
v₀ = 4.0 at 50.0°
So that's not really the velocity we are looking for. We are dealing with a max height problem, which is a y-dimension thing. Therefore, we need the squirrel's upward velocity, which is NOT 4.0 m/s. We find it in the following way:
[tex]v_{0y}=4.0sin(50.0)[/tex] which gives us that the upward velocity is
v₀ = 3.1 m/s
Moving on here's what we also know:
a = -9.8 m/s/s and
v = 0
Remember that at the very top of the parabolic path, the final velocity is 0. In order to find the max height of the squirrel, we need to know how long it took him to get there. We are using 2 of our 3 one-dimensional equations in this problem. To find time:
v = v₀ + at and filling in:
0 = 3.1 - 9.8t and
-3.1 = -9.8t so
t = .32 seconds.
Now that we know how long it took him to get to the max height, we use that in our next one-dimensional equation:
Δx = [tex]v_0t+\frac{1}{2}at^2[/tex] and filling in:
Δx = [tex]3.1(.32)+\frac{1}{2}(-9.8)(.32)^2[/tex] and using the rules for adding and subtracting sig fig's correctly, we can begin to simplify this:
Δx = .99 - .50 so
Δx = .49 meters
If no braking occurs, a total of how much power would be required to keep the railcar moving at 40 m/s
Answer:
40 kW
Explanation:
A railcar has a continuous 1000 N decelerating force any time it is in motion. If no braking occurs, how much power would be required to keep the railcar moving at 40 m/s
Solution:
Power in Physics is the rate of doing work and the work can be mechanical, electrical, etc. The S.I unit of power is the watts (W).
The power required to keep the car moving must match the work done by the friction force (decelerating force) that tends to slow down the railcar.
Work done = Force * displacement
Power = Work done / time = (Force * displacement) / time
Power = Force * (displacement / time)
Power = force * velocity = 1000 N * 40 m/s = 40000 W
Power = 40 kW
: Một mặt phẳng vô hạn tích điện đều, mật độ σ = 4.10-9 C/cm2, đặt thẳng đứng trong không khí. Một quả cầu nhỏ có khối lượng 8 g, mang điện tích q = 10-8 C treo gần vào mặt phẳng, sao cho dây treo lúc đầu song song với mặt phẳng. Lấy g = 9,8m/s2. Khi cân bằng, dây treo quả cầu hợp với mặt phẳng 1 góc bằng bao nhiêu?
Answer:
The angle is 16 degree.
Explanation:
A uniformly charged infinite plane, density σ = 4.10-9 C/cm2, is placed vertically in air. A small ball of mass 8 g, with charge q = 10-8 C, hangs close to the plane, so that the string is initially parallel to the plane. Take g = 9.8m/s2 . In equilibrium, by what angle does the string hanging from the ball make an angle with the plane?
Surface charge density, σ = 4 x 10^-9 C/m^2
charge, q = 10^-8 C
mass, m = 0.008 kg
Let the tension is the string is T and the angle is A.
[tex]T sin A = q E....(1)\\\\T cos A = m g .... (2)\\\\Divie (1) by (2)\\\\tan A =\frac{q E}{m g}\\\\tan A = \frac{10^{-8}\times 4\times 10^{-5}}{2\times 8.85\times 10^{-12}\times 0.008\times9.8}\\\\tan A = 0.288\\\\A = 16 degree[/tex]
Two lenses having f1:F2=2:3 has combination to make no dispersion.Find the ratio of their dispersive power?a)2:3 b)3:2 c)4:9 d)9:4
Answer:
b)3:2
Explanation:
The dispersive power is the reciprocal of the focal length:
[tex]P=\frac{1}{f}[/tex]
Given the ratio of focal lengths:
[tex]\frac{f_1}{f_2} = \frac{2}{3}\\\\\frac{\frac{1}{P_1}}{\frac{1}{P_2}}=\frac{2}{3}\\\\\frac{P_2}{P_1}=\frac{2}{3}\\\\\frac{P_1}{P_2}=\frac{3}{2}[/tex]
Therefore,
P₁ : P₂ = 3 : 2
Hence, the correct option is:
b)3:2
HELP PLEASE!!
When the same amount of heat is added to equal masses of water and copper at the same temperature, the copper is heated to a higher final temperature than the water. On a molecular level, what explains this difference?
A. The forces between copper atoms are stronger than the forces between water molecules.
B. The average kinetic energy of the water molecules is greater than the average kinetic energy of the copper atoms.
C. More of the heat is transferred to the kinetic energy of the copper atoms than to the kinetic energy of the water molecules.
D. More of the heat is transferred to the potential energy of the copper atoms than to the potential energy of the water molecules.
Answer:
C. More of the heat is transferred to the kinetic energy of the copper atoms than to the kinetic energy of the water molecules.
Explanation:
Both equal masses of water and copper were heated at the same temperature. Since copper is a good conductor of heat compared to water, its absorbs more heat. Which in-turn increases the rate of vibrations of the atoms in the copper mass, thus increasing their kinetic energy.
In the case of water, its molecules displaces one another after being heated to a higher temperature compared to neighboring molecules. So that the heated molecule becomes less dense and floats to the surface of water.
This property of copper makes it to be heated to a higher final temperature than the water.
Can somebody help me understand this
A dog wishes to swim across a slow moving stream. The current velocity is 3.0m/s. The distance directly across the stream is 50m. If the dog point himself directly across the stream, it will take .....
Answer:
Time = 16.667 seconds
Explanation:
Given the following data;
Distance = 50 meters
Velocity = 3 m/s
To find the time it will take;
Velocity can be defined as the rate of change in displacement (distance) with time. Velocity is a vector quantity and as such it has both magnitude and direction.
Mathematically, velocity is given by the equation;
Velocity = distance/time
Making time the subject of formula, we have;
Time = distance/velocity
Time = 50/3
Time = 16.667 seconds
help help help please please
Answer:
below
Explanation:
that is the procedure above
Why would an airplane flying at 10,000 meters above the ground have more gravitational potential
energy than the same airplane flying at 1,000 meters above the ground?
Answer:
The gravitational potential energy (gpe) possessed by an object or body is directly proportional to the height of the object or body.
Explanation:
Gravitational potential energy (GPE) is an energy possessed by an object or body due to its position above the earth.
Mathematically, gravitational potential energy is given by the formula;
G.P.E = mgh
Where;
G.P.E represents potential energy measured in Joules.
m represents the mass of an object.
g represents acceleration due to gravity measured in meters per seconds square.
h represents the height measured in meters.
Generally, the gravitational potential energy (gpe) of an object or body is directly proportional to the height of the object or body. Thus, the gravitational potential energy of a body increases as the height of the body increases.
In conclusion, an object with a higher height would have a higher gravitational potential energy.
A stone is thrown with an initial speed of 12 m/s at an angle of 30o above the horizontal from the top edge of a cliff. If it takes the stone 5.6 s to reach the bottom, how far does the stone travel horizontally
Answer:
[tex]d=58m[/tex]
Explanation:
From the question we are told that:
Initial Speed [tex]U=12m/s[/tex]
Time [tex]T=5.6s[/tex]
Angle [tex]\theta=30[/tex]
Generally the Newton's equation for motion is mathematically given by
[tex]d=d'+ut+\frac{at^2}{2}[/tex]
[tex]d=12cos30*5.6[/tex]
[tex]d=58m[/tex]
a.in which portion of the curve,
1. is the velocity uniform.
2.is the velocity increasing.
3.is velocity decreasing.
4.is acceleration zero.
B. at which point does the body start to move and stop.
________________________
I will mark as brainlist
Answer:
the answer is 4 acceleration is 0
Explanation:
this is because when parallel line is drawn through x axis the velocity will bw uniform
plz brainliest
The search for black holes involves searching for The search for black holes involves searching for Group of answer choices single stars that emit large amounts of X-rays. a stellar core greater than 3 solar masses large spherical regions from which no light is detected. pulsars with periods less than one millisecond. pulsars that are orbited by planets.
Answer:
Large spherical regions from which no light is detected
Explanation:
A black hole is an object that has an extremely high density such that it possesses very powerful gravitational force that prevents the escape of all objects including light from it, and consumes nearby objects.
Due to the power of the gravitational force of a black hole, at the center, objects are infinitesimally compressed resulting in the inapplicability of the concept of space and time and the location is known as a singularity
Therefore, the search for black holes involves searching for large spherical regions from which no light is detected.
Does the colour of an object affect the rate of evaporation?
What factors could the skater change to apply the same amount of torque but increase the rate of his spin
Answer:
The moment of inertia should be decreased.
Explanation:
The torque is given by
Torque = Moment of inertia x angular velocity
To keep the torque constant, the spin rate be increased when the moment of inertia decreases.
The moment of inertia of the body are the efforts to put the object in rotation.