Answer:
True
Explanation:
Average speed is the rate at which an object is moving at a given instant in time.
Answer: false.
Explanation: i’m pretty sure that’s instantaneous speed.
A certain gas is compressed adiabatically. The amount of work done on the gas is 800 J. What is the change in the internal (thermal) energy of the gas?
Answer:
800J
Explanation:
Using the formula for change in the internal energy of a system
∆U = Q - W
Q = heat added to the system
W =workdone by system.
We know the process is an adiabatic one then, there no addition/ removal of heat, then Q= 0
(∆U = -W )
Then substitute for W, we have
∆U = -[-800]
∆U= 800J
∆U = 800J
Q1. Helmut rides 5km in 2h on his bike. His speed was *
a) 10km/h
b) 2.5km/h
c) 0.4km/h
d) 2.5km
Q2. A plane is travelling at 250km/h and must reach a target that is 3h 58min away. The distance to the target is. *
a) 1000km
b) 89500km
c) 62.5km
d) not enough information
Answer:
Speed of bike = 2.5 km/h
Distance travel = 1,000 km (Approx.)
Explanation:
Given:
Distance cover by Helmut = 5 km
Time taken = 2 hour
Find:
Speed of bike
Computation:
Speed = Distance / Time
Speed of bike = 5 / 2
Speed of bike = 2.5 km/h
Given:
Speed of plane = 250 km/h
time taken = 3 hr 58 min = 3.967 hr
Find:
Distance travel
Computation:
Distance = Speed x time
Distance travel = 250 x 3.967
Distance travel = 991.669
Distance travel = 1,000 km (Approx.)
Mars can have bigger mountains than the Earth because it has a smaller mass and surface gravity.
True
False
Answer:
True
Explanation:
51.Shoveling snow can be extremely taxing because the arms have such a low efficiency in this activity. Suppose a person shoveling a footpath metabolizes food at the rate of 800 W. (a) What is her useful power output? (b) How long will it take her to lift 3000 kg of snow 1.20 m? (This could be the amount of heavy snow on 20 m of footpath.) (c) How much waste heat transfer in kilojoules will she generate in the process?
Complete question is;
Shoveling snow can be extremely taxing since the arms have such a low efficiency in this activity. Suppose a person shoveling a sidewalk metabolizes food at the rate of 800 W. (The efficiency of a person shoveling is 3%.)
(a) What is her useful power output? (b) How long will it take her to lift 3000 kg of snow 1.20 m? (This could be the amount of heavy snow on 20 m of footpath.) (c) How much waste heat transfer in kilojoules will she generate in the process?
Answer:
A) P_out = 24 W
B) t = 1470 s
C) Q = 1140.72 KJ
Explanation:
We are given;
Input Power; P_in = 800 W
Efficiency; η = 3% = 0.03
A) Formula for efficiency is;
η = P_out/P_in
Making P_out the subject, we have;
P_out = η•P_in
P_out = 0.03 × 800
P_out = 24 W
B) We know that;
Power = work done/time taken
Thus;
P_out = mgh/t
We are given;
m = 3000 kg
h = 1.20 m
Thus, time is;
t = (3000 × 9.8 × 1.2)/24
t = 1470 s
C) amount of heat wasted is calculated from;
Q = (P_in - P_out)t
Q = (800 - 24) × 1470
Q = 1,140,720 J
Q = 1140.72 KJ
Some material consisting of a collection of microscopic systems is kept at a high temperature, so that all excited states are populated and can participate in emission of photons. A photon detector capable of detecting photon energies from infrared through ultraviolet observes photons emitted with energies of 0.3 eV, 0.5 eV, 0.8 eV, 2.0 eV, 2.5 eV, and 2.8 eV. These are the only photon energy observed.
a) Draw and label a possible energy-level diagram for one of the microscopic systems, which has 4 bound states. On the diagram, indicate the transitions corresponding to the emitted photons. Explain briefly.
b) The material is now cooled down to a very low temperature, and the photon detector stops detecting photon emissions. Next a beam of light with a continuous range of energies from infrared thorugh ultraviolet shines on the material, and the photon detector observes the beam of light after it passes through the material. What photon energies in this beam of light are observed to be significantly reduced in intensity ("dark absorption lines")? Explain briefly.
Answer:
The responses to this question can be defined as follows:
Explanation:
During energy exchange E=hv, electrodes spring through one orbit to another
Please find the image file in the attachment.
Its absorption layer comprises 0.3 eV, 0.5 eV., 0.8 eV, 2.0 eV, 2.5 eV again, as light passes via material at low temperature those lines absorbed in the strata called absorption stratum.
During the course of a demonstration the professor is called away. When he returns he finds a beaker of water that was at room temperature is now at a slightly higher temperature. There is a stirring rod on the desk and a cigarette lighter. The professor can assume that the temperature increase is due to either heat added or mechanical work done. mechanical work done on the system. heat added to the system.
Answer:
Either heat added or mechanical work done.
Explanation:
Since he found stirring rod on the desk and a cigarette lighter. This means that the beaker was probably either heated with the aid of fire from the lighter.
Also, the stirring rod could have been used to stir the water which will increase the kinetic energy which also means an increase in temperature.
Thus, it's either heat was added or mechanical work was done as a result of stirring.
The gravitational force between two objects is proportional to the square of the distance between the two objects.
a. True
b. False
Answer: True!
Explanation: The force is proportional to the square of the distance between 2 point masses
Carla has a stick of butter. What can Carla do to the butter to show a chemical change?
Answer:
melting butter in a saucepan, as the butter cools it turns brown
Explanation:
although melting the butter is a physical change, but the butter being cooked and turning brown Is a chemical change, because due to the heat, its particles are being broken down, which is irreversible, and shows a chemical change.
If the motion of B is uniformly accelerated, at what time will both graphs have
exactly the same slope? Explain.
Answer:
Im just here for the points man sorry
Explanation:
A ball with a mass of 0.585 kg is initially at rest. It is struck by a second ball having a mass of 0.420 kg , initially moving with a velocity of 0.270 m/s toward the right along the x axis. After the collision, the 0.420 kg ball has a velocity of 0.220 m/s at an angle of 36.9 ∘ above the x axis in the first quadrant. Both balls move on a frictionless, horizontal surface.
Required:
a. What is the magnitude of the velocity of the 0.605kg ball after the collision?
b. What is the direction of the velocity of the 0.605kg ball after the collision?
c. What is the change in the total kinetic energy of the two balls as a result of the collision?
Answer:
a) [tex](v_1)=0.3989m/s[/tex]
b) [tex]\theta_1=80.5 \textdegree[/tex]
c) [tex]K.E=0.036J[/tex]
Explanation:
From the question we are told that:
Initial speed of 1st ball [tex]u_{1}=0 m/s[/tex]
Mass of 1st ball [tex]m_1=0.585kg[/tex]
Mass of 2nd ball [tex]m_2=0.420kg[/tex]
Initial speed of 2nd ball [tex]u_{2}=0.270 m/s[/tex]
Final speed of 2nd ball [tex]v_{2}=0.220 m/s[/tex]
Angle of collision [tex]\angle=36.9 \textdegree[/tex]
a)
Generally the equation for law of conservation is mathematically given by
[tex]m_1u_1+m_2u_2=m_1v_1^2+m_2v_2^2[/tex]
The final velocity [tex]v_1[/tex] is given as
[tex]0+(0.420)(0.270)=(0.585)(v_1)^2+(0.420)(0.220)^2[/tex]
[tex](v_1)^2=\frac{(0.420)(0.270)-(0.420)(0.220)^2}{0.585}[/tex]
[tex](v_1)^2=0.1591[/tex]
[tex](v_1)=0.3989m/s[/tex]
b)
Generally the equation for law of conservation is mathematically given by
[tex]m_1u_1+m_2u_2=m_1v_1cos\theta_1+m_2\theta_2[/tex]
[tex]0+(0.420)(0.270)=(0.585)(1.511)cos\theta_1+(0.420)(0.220)cos36 \textdegree[/tex]
[tex]cos\theta_1= \frac{(0.420)(0.270)-(0.420)(0.220)cos36 \textdegree}{(0.585)(0.3989)}[/tex]
[tex]cos\theta_1=0.1656[/tex]
[tex]\theta_1=80.5 \textdegree[/tex]
c)
Generally the equation for kinetic energy is mathematically given by
[tex]K.E=\frac{1}{2} mv^2[/tex]
1st Ball
[tex]K.E=\frac{1}{2} (0.585)(0.3989)^2[/tex]
[tex]K.E=0.0465J[/tex]
2nd ball
[tex]K.E=\frac{1}{2} (0.420)(0.220)^2[/tex]
[tex]K.E=0.101J[/tex]
Therefore the change in the total kinetic energy of the two balls as a result of the collision is
[tex]0.101-0.0465[/tex]
[tex]K.E=0.036J[/tex]
Which theory states that the principle cause of forgetting is passage of time? A. motivated forgetting B. retrieval failure C. decay theory D. ineffective encoding
Type the correct answer in each box. Round your answers to the nearest hundredth.
A ball with a mass of 1.5 kilograms is tied to the end of a rope. The ball is pulled to a height of 0.5 meters above the ground and released.
The ball has
joules of potential energy at position B. At position A, all of the energy changes to kinetic energy. The velocity of the ball at position A is
meters/second. Assume there’s no air resistance. Use g = 9.8 m/s2 , PE = m × g × h, and .
Hi there!
[tex]\large\boxed{PE = 7.35 J, \text{ }v \approx 3.13 m/s}[/tex]
To find the potential energy of the ball at B, we can use the equation:
PE = mgh
Plug the given gravity, mass, and height:
PE = (1.5)(0.5)(9.8) = 7.35 J
At A, all of this potential energy is changed to kinetic energy, so we can use the following equation:
v = √2KE/m
Plug in the solved for energy and mass:
v = √2(7.35)/1.5
Solve:
v ≈ 3.13 m/s
a ball rolls horizontally of the edge of the cliff at 4 m/s, if the ball lands at a distance of 30 m from the base of the vertical cliff, what is the the hight of the cliff
Answer:
Approximately [tex]281.25\; \rm m[/tex]. (Assuming that the drag on this ball is negligible, and that [tex]g = 10\; \rm m \cdot s^{-2}[/tex].)
Explanation:
Assume that the drag (air friction) on this ball is negligible. Motion of this ball during the descent:
Horizontal: no acceleration, velocity is constant (at [tex]v(\text{horizontal})[/tex] is constant throughout the descent.)Vertical: constant downward acceleration at [tex]g = 10\; \rm m \cdot s^{-2}[/tex], starting at [tex]0\; \rm m \cdot s^{-1}[/tex].The horizontal velocity of this ball is constant during the descent. The horizontal distance that the ball has travelled during the descent is also given: [tex]x(\text{horizontal}) = 30\; \rm m[/tex]. Combine these two quantities to find the duration of this descent:
[tex]\begin{aligned}t &= \frac{x(\text{horizontal})}{v(\text{horizontal})} \\ &= \frac{30\; \rm m}{4\; \rm m \cdot s^{-1}} = 7.5\; \rm s\end{aligned}[/tex].
In other words, the ball in this question start at a vertical velocity of [tex]u = 0\; \rm m \cdot s^{-1}[/tex], accelerated downwards at [tex]g = 10\; \rm m \cdot s^{-2}[/tex], and reached the ground after [tex]t = 7.5\; \rm s[/tex].
Apply the SUVAT equation [tex]\displaystyle x(\text{vertical}) = -\frac{1}{2}\, g \cdot t^{2} + v_0\cdot t[/tex] to find the vertical displacement of this ball.
[tex]\begin{aligned}& x(\text{vertical}) \\[0.5em] &= -\frac{1}{2}\, g \cdot t^{2} + v_0\cdot t\\[0.5em] &= - \frac{1}{2} \times 10\; \rm m \cdot s^{-2} \times (7.5\; \rm s)^{2} \\ & \quad \quad + 0\; \rm m \cdot s^{-1} \times 7.5\; s \\[0.5em] &= -281.25\; \rm m\end{aligned}[/tex].
In other words, the ball is [tex]281.25\; \rm m[/tex] below where it was before the descent (hence the negative sign in front of the number.) The height of this cliff would be [tex]281.25\; \rm m\![/tex].
A proton moving at v1 = 7.0 Mm/s collides elastically head-on with a second proton moving in the opposite direction at v2 = 8.3 Mm/s. (a) Find the velocity of the first proton after the collision. (b) Find the velocity of the second proton after the collision
Answer:
(a) The final velocity of the first proton after the collision = 8.3 m/s in the opposite to its initial direction
(b) The final velocity of the second proton after the collision = 7 m/s in the opposite to its initial direction
Explanation:
The given parameter of the protons are;
The velocity of the first proton, v₁ = 7.0 Mm/s
The velocity of the second proton, v₂ = -8.3 Mm/s
The type of collision = Elastic collision
In an elastic collision, the kinetic and momentum energies are conserved, therefore, we have, for the initial and final momentums;
(m₁·v₁ + m₂·v₂)₁ = (m₁·v₁ + m₂·v₂)₂
1/2·(m₁·v₁² + m₂·v₂²)₁ = 1/2·(m₁·v₁² + m₂·v₂²)₂
Where, m₁ = m₂ or the protons, we get;
(v₁ + v₂)₁ = (v₁ + v₂)₂
(v₁² + v₂²)₁ = (v₁² + v₂²)₂
Therefore;
7.0 - 8.3 = v₁ + v₂
-1.3 = v₁ + v₂...(1)
7.0² + (-8.3)² = v₁² + v₂²
117.49 = v₁² + v₂²...(2)
From equation (1), we have;
v₁ = -1.3 - v₂
Plugging the value v₁ = -1.3 - v₂ in equation (2) gives;
117.49 = v₁² + v₂² = (-1.3 - v₂)² + v₂² = 2·v₂² + 12·v₂ + 1.69
∴ 2·v₂² + 2.6·v₂ + 1.69 - 117.49 = 0
2·v₂² + 2.6·v₂ - 115.8 = 0
Using the quadratic formula, we have;
v₂ = (-2.6 ± √(2.6² - 4×2×(-115.8)))/(2 × 2)
∴ v₂ ≈ -8.3 m/s or 7 m/s
When v₂ ≈ -8.3, v₁ = -1.3 - v₂ ≈ -1.3 - (-8.3) = 7
When v₂ ≈ 7, v₁ = -1.3 - v₂ ≈ -1.3 - (7) = -8.3
Therefore, the final velocity of the first proton after the collision = 8.3 m/s in the opposite to its initial direction
(b) The final velocity of the second proton after the collision = 7 m/s in the opposite to its initial direction.
3. Two spherical objects have masses of 4.7 x 105 kg and 7.9 x 103 kg. The
gravitational attraction between them is 68 N. How far apart are their
centers?
Answer:
0.06
Explanation:
Working on the problem at hand i calculated and got my answer to around simplified at 0.06
An object moves in a circle with a period of 0.025 hours. What is its frequency in Hz?
Frequency, is defined as the rate of rotation, or the number of rotations in some unit of time. Angular frequency, , is the rotation rate measured in radians. These three quantities are related by f = 1 T = ω 2 π .
what is frequency ?The frequency is the number of oscillation per unit time and it is used for defining the cyclic process like rotation, oscillation, wave etc.
The SI unit of the frequency is denoted as Hertz and the symbol λ represents it where one hertz means the wave completed one cycle in one second.
The frequency which explains the phenomenon of oscillatory and vibration like the mechanical vibration, sound signals, light, frequency waves etc. The “period” represented as the time required by the wave for one oscillation, i.e., it is inversely proportional to the frequency.
If the flashes, then the period is the time between the two flashes. And the frequency is the total number of flashes per second.
For more details regarding frequency, visit
brainly.com/question/14400059
#SPJ2
What is the difference between 1 celcius and 1 kelvin
Answer:
One degree unit on the Celcius scale is equivalent to one degree unit on the kelvin scale. The only difference between these two scales is the zero point. The zero point on the Celcius scale was defined as the freezing point of water, which means that there are higher and lower temperatures around it.
Which of the following is an example of a healthy behavior?
OA
Binge drinking of alcohol
OB.
Smoking cigarettes
OC.
Driving a car recklessly
OD.
None of the above
PE Not Physics
Answer moderate alcohol can be good for you health
Explanation: but I wouldn't do none of those things to be honest
SMARTEST
Answer:
none of the above
Explanation:
its an easy question haha
When the electrons reach the collector, they flow towards the positivly charged grid. The resulting current is measured. Note that as the electrons accelerate from the cathode toward the grid, they collide with the mercury atoms. Assume that these collisions are completely elastic. How does the collected current vary if the ΔVgrid is slowly increased? View Available Hint(s) When the electrons reach the collector, they flow towards the positivly charged grid. The resulting current is measured. Note that as the electrons accelerate from the cathode toward the grid, they collide with the mercury atoms. Assume that these collisions are completely elastic. How does the collected current vary if the is slowly increased? The current increases. The current remains constant. The current decreases.
Answer:
the current INCREASES.
Explanation:
In this experiment, the electrons are generated by a filament with very low speed, when they are subjected to a difference and potential ΔV they acquire the necessary speed to reach the regulation and the current can be measured.
Some electrons collide elastically with the atoms of the mercury gas that is much heavier and are scattered in any direction, so they do not reach the grid, by increasing the voltage this scattered electrons can acquire the necessary speed in the direction of grid to reach it and therefore are also measured, increasing the current.
Therefore, as the power difference increases, the current INCREASES.
mention & reasons why the ability to adapt to change is
important for improvement of your quality of life.
Answer:
The ability to adapt is important because :
1) It helps in the survival of human beings.
2) It brings more variation to the human kind.
3) It helps the species from getting endangered or extinct.
4) It brings transformation in the adapting kind.
Hope this helps you☺️☺️
Which of the following phenomena best demonstrates that light possesses wave characteristics?
A.The different colors of visible light
B.The transfer of electrons
C.The release of infrared light form radioactive materials
D.It shines and takes up space
The release of infrared light from radioactive materials is what demonstrates light possessing wave characteristics.
What is a Wave?This is defined as the propagation of disturbances from one place to another in an organized way.
The release of waves in a diffraction pattern is why option C was chosen as the most appropriate choice.
Read more about Wave here https://brainly.com/question/15663649
You're an electrical engineer designing an alternator (the generator that charges a car's battery). Mechanical engineers specify a 10-cmcm-diameter rotating coil, and you determine that you can fit 250 turns in this coil. To charge a 12-VV battery, you need a peak output of 17 VV when the alternator is rotating at 1500 rpm.
What do you specify for the alternator's magnetic field?
Answer:
13.78 mT
Explanation:
The peak voltage ε = ωNAB where ω = angular speed of coil = 1500 rpm = 1500 × 2π/60 rad/s = 50π rad/s = 157.08 rad/s, N = number of turns of coil = 250, A = area of coil = πr² where r = radius of coil = 10 cm = 0.10 m,
A = π(0.1 m)² = 0.03142 m² and B = magnetic field strength
So,
B = ε/ωNA
substituting the values of the variables into the equation given that ε = 17 V
So, B = ε/ωNA
B = 17 V/(157.08 rad/s × 250 turns × 0.03142 m²)
B = 17 V/(1233.8634 rad-turns-m²/s)
B = 0.01378 T
B = 13.78 mT
System A consists of a mass m attached to a spring with a force constant k; system B has a mass 2m attached to a spring with a force constant k; system C has a mass 3m attached to a spring with a force constant 6k; and system D has a mass m attached to a spring with a force constant 4k.
Rank these systems in order of increasing period of oscillation. (Use only the symbols < and =, for example A < B = C.)
Solution :
We know that the time period of oscillation of a spring mass system is given by :
[tex]$T = 2 \pi \sqrt{\frac{m}{k}}$[/tex] , where m is mass and k is the spring constant
∴ [tex]$T_A = 2 \pi \sqrt{\frac{m}{k}}$[/tex] .........(i)
[tex]$T_B = 2 \pi \sqrt{\frac{2m}{k}}$[/tex] ..........(ii)
[tex]$T_C = 2 \pi \sqrt{\frac{3m}{6k}} = 2 \pi \sqrt{\frac{m}{2k}}$[/tex] ..........(iii)
[tex]$T_D = 2 \pi \sqrt{\frac{m}{4k}}$[/tex] ...............(iv)
Comparing the equations (i), (ii), (iii) and (iv)
We get
[tex]$T_B > T_A > T_C > T_D$[/tex]
So in increasing order of time period, we get
[tex]$T_D < T_C < T_A < T_B$[/tex]
how to makee them love you I AM JK U ARE BEAUTIFUL U DONT NEED A MAN GIRL GO STUDY INSTEAD OF CHECKING UR PHONE 100 TIMES A DAY. ILYYY DONT FORGET THAT
Explanation:
lol ....you are right.......
what is the wavelength of a wave with the frequency of 330 Hz and a speed of 343 m/s
Answer:
The wavelength of a wave with the frequency of 330hz and a speed of 343m/s would be 1.04m
Explanation:
You can get the wavelength of a wave by dividing the speed of the wave by its frequency, which in this case would be:
343/300, which as a decimal number, it'd be 1.04.
I hope I helped you, and a "Brainliest" is always appreciated! ☺
How much current is drawn by a television
with a resistance of 43 Ω that is connected
across a potential difference of 112 V?
Answer in units of A.
Answer:
Explanation:
v = ir
v/r = i
112/43 = i
2.60 ≈ i
What is the wavelength associated with an electron with a velocity of 4.8x10*5 m/s?
(mass of the electron is 9.1 X 10-*31kg)
Answer:
Explanation:
Given the following data;
Mass = 9.1 X 10^{-31} kg
Velocity = 4.8x10⁵ m/s
Planck’s constant ( h ) = 6.6262 * 10^{-34}
To find the wavelength;
Applying de broglie's equation;
Wavelength = h/mv
Wavelength = ) = 6.6262 * 10^{-34}/(9.1 X 10^{-31} * 4.8x10⁵)
Wavelength = 1.52 * 10^{-71} meters
Question 7 of 10
Which of these is a product of beta decay?
O A. An alpha particle
OB. A helium nucleus
C. An electron or a positron
O D. A beam of electromagnetic radiation
Answer:
c.an electron or positron
Answer:
your answer would be c
Explanation:
un cubo de aluminio tiene un volumen de 45cm3 cuál es su masa en gramos
On the Moon’s surface, lunar astronauts placed a corner reflector, off which a laser beam is periodically reflected. The distance to the Moon is calculated from the round-trip time. What percent correction is needed to account for the delay in time due to the slowing of light in Earth’s atmosphere? Assume the distance to the Moon is precisely 3.84×108 m , and Earth’s atmosphere (which varies in density with altitude) is equivalent to a layer 30.0 km thick with a constant index of refraction n = 1.000293.
Answer:
[tex]T_d=2.8*10^-^6\%[/tex]
Explanation:
From the question we are told that
Distance b/w Earth and the moon [tex]d_e=3.84×10^8 m[/tex]
Thickness of Earth's atmosphere[tex]d_t=30km[/tex]
Constant index of refraction [tex]n = 1.000293.[/tex]
Generally the equation for percentage of time delay [tex]T_d[/tex] is mathematically given as
[tex]T_d=\frac{d(n-1)}{rm}*100\%[/tex]
[tex]T_d=\frac{(35*10^3)(1.000293-1)()100)}{3.674*10^8} *\%[/tex]
[tex]T_d=2.8*10^-^6 \%[/tex]
Therefore the general percentage correction needed because of tym deley is given as
[tex]T_d=2.8*10^-^6\%[/tex]