Answer:
5,000-Hz
Explanation:
skier accelerates down the hill at a speed of 18 and reaches the bottom of the hill at a speed of 36 in 6 seconds
What an acceleration of the skier
Answer:
3 m/s²
Explanation:
Initial Velocity, u = 18
Final velocity, v = 36
Time, t = 6 seconds
Acceleration is the change in velocity of a body with time. It obtained using the relation :
Acceleration = (v - u) / t
Acceleration = (36 - 18) / 6
Acceleration = 18 / 6
Acceleration = 3m/s²
Hence, acceleration of the skier is 3m/s²
Where do humans and other animals get their food? From only other animals From plants and other animals From only plants From the sun.
HELP PLZZZ
Answer:
Humans (which are omnivores) get their food from plants and other animals.
Some animals (omnivores) get their food from plants and other animals.
Some animals (carnivores) get their food from only other animals.
Some animals (herbivores) get their food from only plants.
Answer:
c
Explanation:
Every second the sun gives out 400 million joules of energy, but how much of that actually reaches the earth?
Answer:
about 50 million
Explanation:
100% guessing lol
Answer:
the best thing about this place was to have the kids to do it and
Which best describes the energy of a sound wave as it travels through a medium?
It increases.
lt decreases.
It remains the sam.
It depends on the medium,
Answer:
it depends on the medium :D
Who sponsored Felix Baumgartner in the second space jump that took placed in
2008?
Alban Geissler, who developed the SKYRAY carbon fiber wing with Christoph Aarns, suggested after Baumgartner's jump that the wing he used was a copy of two prototype SKYRAY wings sold to Red Bull (Baumgartner's sponsor) two years earlier. - wiki
Which of the following is a theory stating that one plate is forced beneath another plate?
(Choose one) :
1.) theory of Permian Extinction
2.) theory of plate tectonics
3.) theory of subduction
4.) theory of Pangaea
Answer:
theroy of plate tectonics
A cylindrical, 0.500-m rod has a diameter of 0.02 m. The rod is stretched to a length of 0.501 m by a force of 3000 N. What is the Young's modulus of the material?
Answer:
Y = 4.775 x 10⁹ Pa = 4.775 GPa
Explanation:
First, we calculate the stress on the rod:
[tex]stress = \frac{Force}{Area} = \frac{3000\ N}{\pi r^2} \\\\stress = \frac{3000\ N}{\pi (0.01\ m)^2}\\\\stress = 9.55\ x\ 10^6\ Pa = 9.55 MPa\\[/tex]
Now, we calculate the strain:
[tex]strain = \frac{Change\ in Length}{Original\ Length}\\\\strain = \frac{0.501\ m - 0.5\ m}{0.5\ m}\\\\strain = 0.002\\[/tex]
Now, we will calculate the Young's Modulus (Y):
[tex]Y = \frac{stress}{strain}\\\\Y = \frac{9.55\ x\ 10^6\ Pa}{0.002} \\[/tex]
Y = 4.775 x 10⁹ Pa = 4.775 GPa
1.45 L of 16°C water is placed in a refrigerator. The refrigerator's motor must supply an extra 10.7 W power to chill the water to 6°C in 0.7 hr. What is the refrigerator's coefficient of performance?
Answer:
The coefficient of performance of the refrigerator is 2.251.
Explanation:
In this case, the coefficient of performance of the refrigerator ([tex]COP[/tex]), no unit, is equal to the ratio of the heat rate received from the water to the power needed to work, that is:
[tex]COP = \frac{\dot Q_{L}}{\dot W}[/tex] (1)
[tex]COP = \frac{\rho\cdot V\cdot c_{w}\cdot \Delta T}{\dot W \cdot \Delta t}[/tex] (2)
Where:
[tex]\dot Q_{L}[/tex] - Heat rate received from the water, in watts.
[tex]\dot W[/tex] - Power, in watts.
[tex]\rho[/tex] - Density of water, in kilograms per cubic meter.
[tex]V[/tex] - Volume of water, in cubic meters.
[tex]c_{w}[/tex] - Specific heat of water, in joules per kilogram-degree Celsius.
[tex]\Delta T[/tex] - Temperature change, in degrees Celsius.
[tex]\Delta t[/tex] - Cooling time, in seconds.
If we know that [tex]\rho = 1000\,\frac{kg}{m^{3}}[/tex], [tex]V = 1.45\times 10^{-3}\,m^{3}[/tex], [tex]c_{w} = 4187\,\frac{J}{kg\cdot ^{ \circ}C}[/tex], [tex]\Delta T = 10\,^{\circ}C[/tex], [tex]\dot W = 10.7\,W[/tex] and [tex]\Delta t = 2520\,s[/tex], then the coefficient of refrigeration of the refrigerator is:
[tex]COP = \frac{\rho\cdot V\cdot c_{w}\cdot \Delta T}{\dot W \cdot \Delta t}[/tex]
[tex]COP = 2.251[/tex]
The coefficient of performance of the refrigerator is 2.251.
A 5000kg elephant steps into a large spring and compresses it from 1m long to 50cm long what is the spring constant of the spring
Answer: 98 kN/m
Explanation:
Given
Mass of elephant [tex]m=5000\ kg[/tex]
Spring compresses from [tex]1\ m\ (100\ cm) \text{to}\ 50\ cm[/tex]
i.e. change in length is [tex]100-50=50\ cm[/tex]
spring force is given by [tex]kx[/tex]
where k=spring constant
x=change in length
The weight of elephant must be equal to the spring force
[tex]\Rightarrow W=kx\\\Rightarrow 5000\times 9.8=k\times 0.5\\\Rightarrow k=98,000\ N/m\ or\ 98\ kN/m[/tex]
Light travels at a speed of 3.0 ´ 108 m/s. If it takes light from the sun 5.0 ´ 102 s to reach Earth, what is the distance between Earth and the sun?
Answer:
The distance between the Earth and the Sun is:
1.5 multiplied by 10 raised to the power 8 km
Explanation:
(5.0 x 10²) x (3.0 x 10⁸) = 1.5 x 10¹¹ meters = 1.5 x 10⁸ km.
Can you somebody answer this question for me please?
Answer:
The answer is B - the bending of rock layers happens due to stress, and this process is called folding. Faults are when it looks broken/displaced
Eee A student conducts an investigation to determine how the force of gravity affects different objects dropped from different heights. The student tests each object one time and announces that all objects experienced gravity the same way. What is wrong with the student's reasoning?
Answer:
For which the reasoning of the boy is correct for small heights, but as height increases his analysis is not correct.
Explanation:
The force of gravity comes from Newton's second law with the force the universal attraction
F = ma
F = [tex]G \frac{m_1 M}{(R_e +h)^2}[/tex]
we substitute
[tex]G \frac{m_1 M}{ (R_e+ h)^2}[/tex] = m₁ a
where Re is the radius of the Earth 6.37 106 m
a = [tex]G\frac{M}{R_e^2} \ ( 1 + \frac{h}{R_e})^{-2}[/tex]
In general, the height is much less than the radius of the earth, therefore the term ha / Re is very small and we can use a series expansion leaving only the first fears.
(1 + x)⁻² = 1 -2x + [tex]\frac{2 \ 1}{2!}[/tex] x²
we substitute
a = g₀ ([tex]1 - 2 \frac{h}{R_e}[/tex] )
with
g₀ = [tex]G \frac{M}{R_e^2}[/tex]
let's launch the expression.
* For small height compared to the radius of the earth we can neglect the last term
g = g₀
* For height comparable to the radius of the Earth
g = g₀ [tex](1 - \frac{2h}{Re} )[/tex]
We see that the acceleration of gravity is decreasing.
For which the reasoning of the boy is correct for small heights, but as height increases his analysis is not correct.
The student's reasoning gone wrong when the analysis is undertaken for the increasing heights, to drop the object.
The given problem is based on the concept of gravity and gravitational force. The force of gravity comes from Newton's second law with the force the universal attraction as,
F = ma
[tex]F=G\dfrac{mM}{(R+h)^{2}}\\\\\\ma = G\dfrac{mM}{(R+h)^{2}}[/tex]
Here, a is the linear acceleration, m is the mass of object, M is the mass of Earth, R is the radius of Earth and h is the height from where the objects will be dropped. Then,
[tex]a = \dfrac{GM}{R^{2}} \times(1+h/R)^{-2}[/tex]
In general, the height is much less than the radius of the earth, therefore the term h/ R is very small, hence can be neglected.
[tex]a = \dfrac{GM}{R^{2}}\\\\a=g = \dfrac{GM}{R^{2}}[/tex]
g is the gravitational acceleration.
For small height compared to the radius of the earth we can neglect the last term as,
a = g
And for the height comparable to radius of Earth,
[tex]a = \dfrac{GM}{R^{2}} \times(1+h/R)^{-2}\\\\a=g \times(1+h/R)^{-2}[/tex]
Clearly, the acceleration of gravity is decreasing, for which the reasoning of the boy is correct for small heights, but as height increases his analysis is not correct.
Thus, we can conclude that the student's reasoning gone wrong when the analysis is undertaken for the increasing heights, to drop the object.
Learn more about the gravitational force here:
https://brainly.com/question/15647838
The ___ of a position time graph represents an objects velocity
Answer:
this one is for your egg drop question
first question -
Use this worksheet to design your device and record your data. You can then use this form to help you write your lab report.
Height of egg drop: _5ft._
__________________________________________________________
Q2:
Ideas for Prototype Design
Teepee, large cube , small cube
__________________________________________________________
Q3:
Preliminary Sketches (attach separate paper if needed)
Option A: teepee
__________________________________________________________
Q4:
Advantages: Disadvantages:
● fully covered ● egg might crack
● could stand higher distances ●egg will most likely bounce around around but not crack but most likely to crack
__________________________________________________________
Q5:
Option B: large cube
Option C: smaller cube
__________________________________________________________
Q6:
more advantages and disadvantages
Advantages: Disadvantages:
● egg will be tightly secured so nothing bounces around
● egg might crack depending on the impact to the floor
__________________________________________________________
Q7:
Which of the three designs will you move forward with? Explain your reasoning for selecting this design.
I think i'm going to be moving forward with the teepee design
__________________________________________________________
Q8:
Building the Prototype
What modifications, if any, did you make to the basic design during the construction process?
I made it a little smaller than the original design
__________________________________________________________
Q9:
Predictions
Will your device cushion the egg? How will your device do this?
I think it will cushion the design if i put the plastic bag in with the egg it should prevent it from moving around to much
__________________________________________________________
Q10:
Will your device increase the time it takes for the egg to impact the ground? How will your device do this?
I think the extra weight added to the design might affect it by speeding up the process down to the floor
__________________________________________________________
Q11:
Observations
Record your observations and the results of the experimental tests of your device below.
First i tried the egg without the plastic bag and it cracked so i made the design smaller and added the plastic bag this time
__________________________________________________________
Q12:
Evaluating Your Prototype
What worked well? I would say definitely the plastic bag keeping the egg in place
__________________________________________________________
Q13:
Which features can be improved upon? The structure itself as in where the string and tape were
__________________________________________________________
Q14:
Suggestions
How could the design of this device be improved? More balance i guess because the egg would move alot without the bag
__________________________________________________________
Q15:
Why would this change be an improvement? What force or momentum principle is this improvement based on? If the egg had more balance then it would have a less chance of cracking i think this is a type of impulse toward the ground bc of the egg’s weight
__________________________________________________________
Q16:
Sketch of Final Design
Draw a well-labeled sketch of the final design.
( i provided it :) )
okie peace!
Answer
slope
Explanation:
Which two things might an object do when there are no forces acting on it?
Answer:
for one they will stay there. And another thing it will do is collect rust pretty much destroying it.
Explanation:
bit.♠ly/3♠vhMu♠vJ remove symbols before searching or it wont work, there was a bug stoping me from attaching the image so there it is
Answer:
k and...
Explanation:
Answer:
no thank you.
explanation: Do not want to
If an object possesses 500 J of potential energy, how much work is needed to lift this object?
a) 500 J
b) 250 J
c) 150 J
d) 1000 J
Answer:
a) 500 J
Explanation:
Potential energy can be defined as an energy possessed by an object or body due to its position.
Mathematically, potential energy is given by the formula;
[tex] P.E = mgh[/tex]
Where,
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.
In Science, the potential energy possessed by an object or body is the same as the work done by the object or body.
Since we know that the object possessed 500 Joules of potential energy; it would ultimately require to do a work of 500 Joules to lift the object.
Mathematically, work done = force * distance
But force = mass * acceleration due to gravity
F = mg; d = h
Substituting into the work done formula, we have;
Hence, Workdone = Fd = mgh
Calculate the potential energy of a rock with a mass of 55 kg as it sits on a cliff that is 27 m high
Answer:
The potential energy is zero since the rock isn't moving.
Divers get "the bends" if they come up too fast because gas in their blood expands, forming
bubbles in their blood. If a diver has 0.05 L of gas in his blood under a pressure of 25,000
kPa, then rises to a depth where his blood has a pressure of 5000 kPa, what will be the
volume in liters of gas in his blood?
Answer:
V= 0.25L
Explanation:
What is meant by uniform motion ? Write with an example.
Answer:
This type of motion is defined as the motion of an object in which the object travels in a straight line and its velocity remains constant along that line as it covers equal distances in equal intervals of time, irrespective of the duration of the time.
Explanation:
In Physics, uniform motion is defined as the motion, wherein the velocity of the body travelling in a straight line remains the same. When the distance travelled by a moving thing, is same at several time intervals, regardless of the time length, the motion is said to be uniform motion.
What is happening to the ATOMS INSIDE of a magnet that gives the
material its magnetic properties?
Answer:
The atoms are aligned in a particular direction
Explanation:
The atoms become aligned in a particular direction in regions called domains, thus resulting in an overall resultant magnetism due to the spin of the electrons.
Please help me with 17 and 18!!!!!! (It's related to 16) It's due today!!!!! NO LINK PLEASE!!!!!!!!
Answer:17: A wave can be defined as follows: It is important to realize that a wave is quite a different object than a particle. A baseball thrown though a window transfers energy from one point to another, but this involves the movement of a material object between two points.
Explanation:
18: In this way, we classify waves into electromagnetic and mechanical waves. The main difference between mechanical and electromagnetic waves is that electromagnetic waves do not require a medium to propagate whereas mechanical waves require a medium in order to propagate.
Why do baseball pitchers throw the ball at an angle that is slightly above the horizontal if they want the ball to reach at approximately the same height as it was thrown when it gets to the batter?
Answer:
The angle above the horizontal at which the pitcher throws the ball determines the distance the ball travels before returning to the height at which it was thrown
Explanation:
The baseball is thrown as a projectile and the range, 'R', of the baseball which is the distance the baseball travels before the height above the ground returns to the initial height is given given as follows;
[tex]R = \dfrac{u^2 \cdot sin(2\cdot \theta )}{g}[/tex]
Where;
R = The range of the baseball = The horizontal distance away from the pitcher the ball reaches
u = The initial velocity with which the baseball was thrown
θ = The angle above horizontal a baseball pitcher throws the ball
g = The acceleration due to gravity ≈ 9.81 m/s²
From the the equation, when θ = 0, sin(θ) = sin(0) = 0 and the ball does not cover any horizontal distance before going lower than the height at which it was thrown, therefore, for the ball to travel further, the angle of launch, θ has to be larger than 0.
26. A solid wheel accelerates at 3.25 rad/s2 when a
force of 4.5 N exerts a torque on it. If the wheel
is replaced by a wheel which has all of its mass
on the rim, the moment of inertia is given by
1 = mr? What force should be exerted on the
strap to give the same angular velocity?
Answer:
9.0 N
Explanation:
The location of the mass of the wheel on the wheel = Evenly distributed
The acceleration of the solid wheel, α = 3.25 rad/s²
The applied force on the wheel = 4.5 N
The location mass of the replacement wheel = All on (around) the rim
The moment of inertia of the new wheel, I = m·r² (From an online source)
We have;
The moment of inertia for a solid wheel = 1/2·m·r²
The torque, τ = Moment of inertia, I × Acceleration, α
For the solid wheel, we have;
τ = 1/2·m·r² × 3.25 rad/s²
τ = r × F = r × m × a
For the replacement wheel, we have;
τ = m·r² × 3.25 rad/s² = 2 × 1/2·m·r² × 3.25 rad/s²
∴ τ = 2 × r × F
Given that the radius remains the same, the force applied on the replacement wheel needs to be doubled
The force that should be exerted on the strap to give the same angular velocity, F' = 2 × F
The required force, F' = 2 × 4.5 N = 9.0 N.
An electromagnetic wave with frequency 65.0Hz travels in an insulating magnetic material that has dielectric constant 3.64 and relative permeability 5.18 at this frequency. The electric field has amplitude 7.20×10−3V/m. What is the wavelength of the wave?
Answer:
The wavelength of the wave is [tex]1.06\times10^6 m[/tex]
Explanation:
Lets calculate
We know an electromagnetic wave is propagating through an insulating magnetic material of dielectric constant K and relative permeability [tex]K_m[/tex] ,then the speed of the wave in this dielectric medium is [tex]\nu[/tex] is less than the speed of the light c and is given by a relation
[tex]\nu=\frac{c}{\sqrt{KK_m} }[/tex] --------- 1
In case the electromagnetic wave propagating through the insulating magnetic material , the amplitudes of electric and magnetic fields are related as -
[tex]E_m_a_x= \nu B_m_a_x[/tex]
The magnitude of the 'time averaged value' of the pointing vector is called the intensity of the wave and is given by a relation
[tex]I = S_a_v[/tex]
[tex]\frac{E_m_a_xB_m_a_x}{2K_m\mu0}[/tex]----------- 3
now , we will find the speed of the propagation of an electromagnetic wave by using equation 1
[tex]\nu=\frac{c}{\sqrt{KK_m} }[/tex]
Putting the values ,
=[tex]\nu= \frac{3.00\times10^8}{\sqrt{(3.64)(5.18)} }[/tex]
=[tex]0.6908\times10^8m/s[/tex]
= [tex]6.91\times10^7m/s[/tex]
Now , using this above solution , we will find the wavelength of the wave -
[tex]\lambda=\frac{\nu}{f}[/tex]
Putting the values from above equations -
[tex]\frac{6.91\times10^7m/s}{65.0Hz}[/tex]
[tex]\lambda= 1.06\times10^6 m[/tex]
Hence , the answer is [tex]\lambda= 1.06\times10^6 m[/tex]
a rocket burns propellant at a rate of dm/dt = 3.0 kg/s, ejecting gases with a speed of 8000 m/s relative to the rocket. Find the magnitude of the thrust.
Answer: 24 kN
Explanation:
Given
The rocket burns propellant at the rate of
[tex]\dfrac{dm}{dt}=3\ kg/s[/tex]
Relative ejection of gases [tex]v=8000\ m/s[/tex]
The magnitude of thrust force is given by
[tex]F_t=v\dfrac{dm}{dt}\\\\F_t=8000\times 3=24,000\ N\ or\ 24\ kN[/tex]
If the harmonic is 66 Hz, find the fundamental frequency
Two identical charged pith balls are brought together to touch each other. They are then
allowed to move freely. The charge on pith ball A is –30 nC and on pith ball B is – 5 nC.
What is the charge on each after they separate?
Answer:
-17.5 nC
Explanation:
charge A = -30 nC
charge B = -5 nC
After adding them it would be the average of the two charges because of the getting same voltage difference. so
c = (-30+(-5)) / 2 nC
c= -17.5 nC
answer is -17.5 nC
What happened to the kelp forest when the otter was hunted to near extinction?
Answer: Sea otter is the pioneer species in the kelp forest as it regulates and controls the population of other species in the kelp forest.
Explanation:
If sea otters are hunted and their population is brought to extinction then this will cause major harm the ecosystem of the kelp forest and it will disturb the ecological balance in the kelp forest. The herbivorous animals consumed by the sea otters will increase in population and they will consume a lot of vegetation in the forest. The kelp forest which forms the coastline will not remain effective in providing protection against the storms to the neighboring areas.
Which of the following correctly defines the speed of a wave?
O A. v=1
B. A = vf
O C. v= f 2
OD. =v2
Answer:
V = f x λ
Explanation:
The options are confusing
If an electron vibrates back and forth in an clean wire with a frequency of 60.0 Hz, how many cycles make in 1.0 h?
a. 8.1 x 10^5
b. 6.0 x 10^2
c. 3.7 x 10^3
d.2.2 x 10^5
e. 4.6 x 10^4
Plz Help
If an electron vibrates back and forth in an clean wire with a frequency of 60.0 Hz, then it will make 2.2×10⁵ cycles. in 1.0 h. Hence option D is correct.
What is electric charge ?Electric charge is the physical property of matter that experiences force when it is placed in electric field. F = qE where q is amount of charge, E = electric field and F = is force experienced by the charge. there are two types of charges, positive charge and negative charge which are generally carried by proton and electron resp. like charges repel each other and unlike charges attract each other. the flow charges is called as current. Elementary charge is amount of charge a electron is having, whose value is 1.602 x 10⁻¹⁹ C
Amplitude is a measure of loudness of a sound wave. More amplitude means more loud is the sound wave.
Wavelength is the distance between two points on the wave which are in same phase. Phase is the position of a wave at a point at time t on a waveform. There are two types of the wave longitudinal wave and transverse wave.
Frequency is nothing but the number of oscillation in a unit time.
Given,
frequency f = 60.0 Hz.
time t = 1.0 h = 60*60 = 3600s
F = number of cycles/time
number of cycles = F×time
The number of cycles in 1 Hr is
60*3600 = 2.2×10⁵ cycles.
Hence option D is correct.
To know more about frequency ;
https://brainly.com/question/5102661
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