Answer:
a) -3.267 m/s
b) 2.227 m/s
Explanation:
As per the conservation of momentum
m1v1 + m2v2=0
m1= mass of log
m2 = mass of lumber jack
v1 = velocity of log
v2 = velocity of lumber jack
a) Velocity of first log
[tex]-\frac{70*7}{150} = -3.267[/tex] m/s
b) m1v1 + m2v2 = m3v3
Velocity of log
= [tex]\frac{70*7}{150+70} \\2.227[/tex]
A spacecraft is moving past the earth at a constant speed of 0.60 times the speed of light. The astronaut measures the time interval between ticks of the spacecraft clock to be 3.2 s. What is the time interval (in seconds) that an earth observer measures
Answer:
the time interval that an earth observer measures is 4 seconds
Explanation:
Given the data in the question;
speed of the spacecraft as it moves past the is 0.6 times the speed of light
we know that speed of light c = 3 × 10⁸ m/s
so speed of spacecraft v = 0.6 × c = 0.6c
time interval between ticks of the spacecraft clock Δt₀ = 3.2 seconds
Now, from time dilation;
t = Δt₀ / √( 1 - ( v² / c² ) )
t = Δt₀ / √( 1 - ( v/c )² )
we substitute
t = 3.2 / √( 1 - ( 0.6c / c )² )
t = 3.2 / √( 1 - ( 0.6 )² )
t = 3.2 / √( 1 - 0.36 )
t = 3.2 / √0.64
t = 3.2 / 0.8
t = 4 seconds
Therefore, the time interval that an earth observer measures is 4 seconds
Please help
Which of the following is an example of heat energy being transformed into mechanical energy
A. An electric mixer being used to beat eggs
B. A person turning a crank to sharpen a pencil.
C. A car battery being used to power a car radio
D. Boiling water producing steam used to power a boat
Answer:
D
Explanation:
because it is the only one that has something to do with heat keyword would be boiling
A child has a mass of 35 kg. The child is running across a fiend and has a speed of 3 m/s. What is the kinetic energy of the child?
Answer:
Explanation:
Given the following data;
Mass = 35 kg
Velocity = 3 m/s
To find the kinetic energy of the child;
K.E = ½mv²
if a car travels 200 m to the east in 8.0s what is the car's average velocity.
Answer:
25mph
Explanation:
you do distance divided by time. 200/8=25
Which organisms were first responsible for depleting carbon dioxide from the atmosphere, replacing it with oxygen?
A) Plants
B) Dinosaurs
C) Cyanobacteria
D) Trilobites
13. For an object to appear transparent, what interaction must occur between light waves and the object they hit?
A. They are refracted.
C. They are diffracted
B. They are absorbed.
D. They are transmitted
Answer:
The answer is B
Explanation:
The absorption happens when photons from light hit atoms and molecules, and they vibrate because of that specific interaction. Then the heat ejects from the object in the format of thermal energy.
For an object to appear transparent, light waves must be transmitted through the object. Option D is correct.
What are light waves?Light waves are a type of electromagnetic radiation that can be perceived by the human eye.
Here,
For an object to appear transparent, light waves must be transmitted through the object. Therefore, the correct answer is D. When light waves are transmitted, they pass through the object without being absorbed or reflected, allowing us to see through the object. The degree to which light is transmitted through an object is related to the object's optical properties, such as its refractive index, which determines how much the light is bent as it passes through the object.
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A spring is hung from the ceiling. When a block is attached to its end, it stretches 2.6 cm before reaching its new equilibrium length. The block is then pulled down slightly and released. What is the frequency of oscillation?
Answer:
f = 3.09 Hz
Explanation:
This is a simple harmonic motion exercise where the angular velocity is
w² = [tex]\frac{k}{m}[/tex]
to find the constant (k) of the spring, we use Hooke's law with the initial data
F = - kx
where the force is the weight of the body that is hanging
F = W = m g
we substitute
m g = - k x
k = [tex]- \frac{m g}{x}[/tex]
we calculate
k = [tex]- \frac{9.8 m}{- 2.6 \ 10^{-2}}[/tex]
k = 3.769 10² m
we substitute in the first equation
w² = [tex]\frac{ 3.769 \ 10^2 \ m }{m}[/tex]
w = 19.415 rad / s
angular velocity and frequency are related
w = 2πf
f = [tex]\frac{w}{2\pi }[/tex]
f = 19.415 / 2pi
f = 3.09 Hz
Two concentric, circular wire loops of radii r1 and r2 (r1 < r2) are located in the x-y plane; each carries a current I in a clockwise direction. (a) Find the net dipole moment of this system. (b) Repeat for the reversed current in the inner loop
Answer:
a. πi(r₁² + r₂²)
b. πi(r₂²- r₁²)
Explanation:
(a) Find the net dipole moment of this system.
The magnetic dipole moment, μ = iA where i = current and A = For area
For the circular loop with radius r₁, and current i₁ in a clockwise direction, i₁ = + i positive
μ₁ = i₁A₁
= +i(πr₁²)
= πir₁²
For the circular loop with radius r₂, and current i₂ in a clockwise direction, i₂ = +i
μ₂ = i₂A₂
= +i(πr₂²)
= πir₂²
The net dipole moment, μ = μ₁ + μ₂
μ = μ₁ + μ₂
= πir₁² + πir₂²
= πi(r₁² + r₂²)
(b) Repeat for the reversed current in the inner loop
With the reversed current in the inner loop, the current is negative. So i₂ =-i
μ₁ = i₂A₁ = -i(πr₁²) = -πir₁²
So,
μ = μ₁ + μ₂
= -πir₁² + πir₂²
= πi(-r₁² + r₂²)
= πi(r₂²- r₁²)
A theme park creates a new kind of water wave pool with large waves caused by constructive interference. There are two wave generators in phase with each other along either side of a pool that is 24.0 m wide. A swimmer that is 9.0 m from one generator and 14.0 m from the other notices that she is in a region with almost no wave amplitude, but there are large-amplitude waves on either side of her.
What is the longest wavelength that will produce this interference pattern?
Express your answer to three significant figures and include appropriate units.
Answer:
10.0 m
Explanation:
Since there is no amplitude at the point of the swimmer, we have destructive interference.
So, the path difference ΔL = L₂ - L₁ where L₁ = swimmer's shorter distance from one generator = 9.0 m and L₂ = swimmer's longer distance from the other generator = 14.0 m. ΔL = 14.0 m - 9.0 m = 5.0 m
Also, since we have destructive interference, ΔL = (n + 1/2)λ where n = number of wavelengths and λ = wavelength of waves
For maximum wavelength, n = 0
So, ΔL = (n + 1/2)λ
ΔL = (0 + 1/2)λ
ΔL = λ/2
λ/2 = ΔL
λ = 2ΔL
λ = 2 × 5.0 m
λ = 10.0 m
So, the longest wavelength that will produce this interference pattern is λ = 10.0 m
Drag the tiles to the correct boxes. Not all tiles will be used.
Match the molecular shapes to the correct Lewis structures.
trigonal pyramidal
trigonal planar
bent
tetrahedral
linear
Answer
1) AlH3= trigonal planar
2) CH2F2= tetrahedral
3) PH3= trigonal pyramidal
4) O3= bent
Explanation:
I took the test
Hello guys sana ok lng kau
sssssssssssss
Explanation:
Answer:
hello how are you
have a great day
_PCi5 + _H20 + _H3PO4 _HCI
A.) 1,3,1,5
B.) 2,4,1,5
C.) 1,4,1,5
D.) 2,1,2,5
Answer:
C
Explanation:
because of the kids are doing well and staying in the middle of the day early to get a new phone number for home now deep
Which element has 1 valence electron in its outer shell and will react with a
group 17 element in a 1:1 ratio?
A. Strontium
B. Silicon
C. Lithium
D. Sulfur
Answer: C. Lithium
Explanation: Quizzed
C. Lithium has 1 valence electron in its outer shell and so will react with a group 17 element in a 1:1 ratio.
The last number of group that an element belongs to on the periodic table tells the number of valence electrons that it will have.
Lithium is in group 1 of the periodic table which means that it has only a single electron in its valence shell.Group 17 elements have seven valence electrons and so need one more to achieve stability which is why they will react with Lithium (which has that one electron) in a 1:1 ratio.
Some of those elements include:
Fluorine ChlorineBromineIodineIn conclusion therefore, Lithium has 1 valence electron and will react with group 17 elements in a 1:1 ratio.
Find out more at https://brainly.com/question/20516188.
a car traveling in a highway brakes to a stop without skidding. what happens to its kinetic energy? can that energy be recovered and reused?
Answer:
A car traveling on a highway takes to stop without skidding. What happens to its kinetic energy? ... The energy goes to parts of the brakes. No, the energy can only be reused if there is a heat pump present
when a light beam emerges from water into air, the average light speed ____.
a. increases
b. decreases
c. remains the same
d. not provided
Answer:
Increases
Explanation:
The light is emerging from a denser medium to rarer medium so the average light speed increases.
When a light beam emerges from water into air, the average light speed increases.
What is refraction?The bending of a ray passes at an angle from one medium to another in which the speed will be different, as when light passes from air into water and also from water into air can be known as refraction.
When light travels from water to air, the angle from water to air the light gets speeds up and then its changes direction. The light turns away from the normal line. Because the light moves from a denser medium to the rarer medium. But from air to water the speed will be decreased because in that case the light travels from the rarer medium to the denser medium.
Hence, the light beam when passes, the average speed gets increased.
So, Option A is the correct answer.
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What are
the main differences between cell
walls and cell membranes?
Answer:
Cell membrane helps to enclose the cell organelles and cytosol inside a cell. A cell wall is a ridgid, protective layer and it covers the cell membrane
Explanation:
If you lived on Saturn, which planets would exhibit retrograde motion like that observed for Mars from Earth? (Select all that apply.)
Mercury
Venus
Earth
Mars
Jupiter
Uranus
Neptune
Answer:
earth , mercury , and neptune
Explanation:
pls mark brainless
True or False - Water changing between states of matter is an example of a physical change.
true. true is the correct answer
a boy takes 20 minutes to cover 3.2 km on a bicycle find the speed in km/hr
Answer:
9.6 km/h
Explanation:
20 minutes=1/3 minute.
The speed of the bicycle: 3.2:1/3=9.6 km/h.
Answer: 9.6 km/h
If 84 J of work are exerted to pull a wagon, how much force does it take to pull the wagon 7.0 m? Round your answer to the nearest whole number.
Answer: It takes 12 N of force to pull the wagon.
Explanation:
What are the parts of a torch light name them
Answer: Batteries,the case of the torch,reflector,contacts,switch and lens and the light/bulb Hope i helped :)
If a person wanted to engineer a new type of communication device, what field of study would be the most useful?
A ) electrical engineering
B ) chemical engineering
C ) optical engineering
D ) mechanical engineering
Answer: Option A: electrical engineering.
Explanation: The field of electrical engineering, sometimes called electronics engineering, mostly outside the US, is a field of engineering that covers a number of subtopics that include large scale power systems, electronics, control systems, signal processing and telecommunications. In this case the engineer would specifically have to know about electronics (computer chips), signal processing (cell signals) and telecommunications.
A 12 ohm resistor and a 24 ohm resistor are connected in parallel across a 6.0 V battery. The correct statement from the following is a. the current is the same in each resistor. b. the power dissipated is the same in each resistor. c. the larger current is in the larger resistor. d. the voltage difference between the ends of each resistor is the same.
Answer:
d. the voltage difference between the ends of each resistor is the same.
Explanation:
A resistor is a circuit component that offers opposition to the flow of current. Resistors may be connected in series or in parallel.
Resistors in parallel are connected at common junctions. The potential difference (voltage difference between the ends of each resistor) is the same for each resistor in a parallel connection while the current across each resistor is different.
A uniform rod of length 50cm and mass 0.2kg is placed on a fulcrum at a distance of 40cm from the left end of the rod. At what distance from the left end of the rod should a 0.6kg mass be hung to balance the rod?
a.48 cm
b. 50 cm
c. 45 cm
d. the rod can not be balanced with this mass. e.42 cm
NO LINKS.
Bent over row trains what specific muscle?
O A. triceps
O B. trapezius
O C. latissimus dorsi
D. pectoralis major
Polarizing windows, filters, etc. are often used to reduce the amount of light that enters the lens of a camera or into a room or a car. A library atrium has an overhead skylight that lets in too much light during the day which heats up the interior of the library far too much. The building engineer installs new double paned polarizing sky lights to reduce the intensity. If sunlight, which is unpolarized, has an average intensity of 1366 W/m2 what angle should the polarizing axis of the second pane of the window make with the polarizing axis of the first pane of the window in order to reduce the intensity of the sunlight to 33% of the original value
Answer:
θ = 35.7º
Explanation:
For this exercise we must use the law of Malus
I = I₀ cos² θ
where the angle is between the two polarizers.
When the unpolarized light from the sun reaches the first polarizer, only the light polarized in the direction manages to be transmitted, which is why
I₁ = I₀ /2
this light reaches the second polarizer
I₂ = I₁ cos² θ
I₂ = I₀/2 cos² θ
cos² θ = 2 I₂ / Io
indicate that the transmitted light is 33% = 0.33 I₀
cos² θ = 2 0.33
cos θ = √0.66
θ = cos⁻¹ 0.8124
θ = 35.7º
Complete the sentence below using the words provided in parentheses (). For two universes that are the same size, the universe with the faster expansion rate must be _______ (younger/older) than the universe with the slower expansion rate. The slope of the line in the Hubble plot of the ______ (younger/older) universe will be ______ (steeper/flatter)
Answer:
For two universe that is the same size, the universe with the faster expansion rate must be younger than the universe with a slower expansion rate. The slope in the line of the Hubble plot of the older universe will be flatter.
Explanation:
Hubble's law establishes a direct relationship between a galaxy's distance and its redshift-determined recessional velocity. The redshifts of galaxy clusters and distant galaxies are equivalent and proportional to their distances from us, according to Hubble's theorem.
Thus, to copy and complete the given question.
For two universe that is the same size, the universe with the faster expansion rate must be younger than the universe with a slower expansion rate. The slope in the line of the Hubble plot of the older universe will be flatter.
As wavelength decreases the frequency of a wave _______
Question (Fill-In-the Blank):
As wavelength decreases the frequency of a wave _______
Answer:
Increases
Explanation:
When waves travel from one medium to another the frequency never changes. As waves travel into the denser medium, they slow down and wavelength decreases. Part of the wave travels faster for longer causing the wave to turn. The wave is slower but the wavelength is shorter meaning frequency remains the same.
[tex] \boxed{ \boxed{ \huge\mathrm{Answer࿐}}}[/tex]
[tex] \mathrm{wavelength \: \: \dfrac{1}{ \propto} \: \: frequency }[/tex]
So, As wavelength decreases the frequency of a wave Increases.
_____________________________
[tex]\mathrm{ \#TeeNForeveR}[/tex]
You have 3 resistors and a battery to form a closed circuit. Two 2-Ohm resistors are in series with each other. The combination of those two resistors is in parallel with a 4-Ohm resistor. The total voltage of this circuit is 12 Volts. The total current and resistance of this circuit is a. 2 Ohms, 6 Amps b. 8 Ohms, 1.5 Amps c. 6 Ohms, 2 Amps d. 1.5 Ohms, 8 Amps
Answer:
Option 2
Explanation:
Given
Two 2-Ohm resistors are in series and these two resistors are in parallel with a 4-Ohm resistor
Equivalent resistance of two resistors in series = R1 + R2 = 2+2 = 4 Ohm
Equivalent resistance of two 4 Ohm resistors is parallel =1/ (1/4 +1/4) = 2 Ohm
Voltage = 12 Volts.
Hence, current = V/R = 12/2 = 6 Amp
Option 2 is correct
If the period of a given wave is 6 seconds, what is the frequency of the wave?
A. 17 Hz
B. 0.17 Hz
C. 0.017 Hz
D. 1.7 Hz
Answer:
[tex]\text{B. }0.17\:\mathrm{Hz}[/tex]
Explanation:
The frequency of a wave is given by [tex]f=\frac{1}{t}[/tex], where [tex]t[/tex] is the period of the wave.
Substituting [tex]t=6[/tex], we get:
[tex]f=\frac{1}{6}\approx \boxed{\text{B. }0.17\:\mathrm{Hz}}[/tex]