Explanation:
It is given that,
The Displacement x of particle moving in one dimension under the action of constant force is related to the time by equation as:
[tex]x=4t^3+3t^2-5t+2[/tex]
Where,
x is in meters and t is in sec
We know that,
Velocity,
[tex]v=\dfrac{dx}{dt}\\\\v=\dfrac{d(4t^3+3t^2-5t+2)}{dt}\\\\v=12t^2+6t-5[/tex]
(a) i. t = 2 s
[tex]v=12(2)^2+6(2)-5=55\ m/s[/tex]
At t = 4 s
[tex]v=12(4)^2+6(4)-5=211\ m/s[/tex]
(b) Acceleration,
[tex]a=\dfrac{dv}{dt}\\\\a=\dfrac{d(12t^2+6t-5)}{dt}\\\\a=24t+6[/tex]
Pu t = 3 s in the above equation
So,
[tex]a=24(3)+6\\\\a=78\ m/s^2[/tex]
Hence, this is the required solution.
A car is moving on straight highway with a speed of 108 km/h.
Answer:
5.3333 sec
Explanation:
initial speed: u = 108km/hr or 30 m/s
final speed: v = 0m/s
distance travelled: s = 80m
time the car took to stop: = t sec
[tex]v^{2} - u^{2}[/tex] = 2as,
a = ([tex]v^{2} - u^{2}[/tex])/2s
a = (0-900)/160
a = -5.625 [tex]ms^{-2}[/tex]
v = u + at,
t = (v - u)/a
t= (0 - 30)/(-5.625)
t = 5.3333 sec
Dr. Bishop wants to study how small children respond to scary stimuli. She will explain the procedure to parents and ask them to sign a permission form. She will have 3-5 year old kids individually come into her lab
Each child will be given a teddy bear to cuddle with. She will then stand a couple of feet behind the child as he or she plays and make a very loud scary sound. She will observe and measure the child's responses. The
child will come back in a few days and be given the teddy bear again, she will measure any reactions the child has to the bear.
What might an ethics review committee decide about the proposal?
The proposal is approved, as it meets the ethical guidelines defined by the APA
O The proposal is approved, because there is no deception
The proposal is denied, because participants wil ikely suffer psychological harm.
O The proposal is denied, because participants are not allowed to leave the study
The proposal is denied, because it does not meet confidentiality standards
Answer:
The correct option is;
The proposal is denied, because participants will likely suffer psychological harm
Explanation:
Among the recommendations in the report on ethical research with children, it is suggested that the following should be observed by researchers;
1) Seeking consent should be a continuous process
2) Contemplate payment forms other than money to allow more discretion on child safety
3) Have two way communication with the child
4) Ask for assent of the child participating in the research
The above APA suggestions where not met by the researcher in the study.
Answer:
The proposal is denied, because participants will likely suffer psychological harm.
Explanation:
This proposal would cause psychological harm to its participents.
I also took the test and that was the correct answer.
The marginal cost curve
(a) Lies below the ATC curve when the ATC curve slopes upward.
(b) Intersects the AFC and ATC curves at their respective minimum points.
(c) Lies above the AVC curve when the AVC curve slopes downward.
(d) Intersects the AFC and AVC curves at their respective minimum points.
(e) Intersects the AVC and ATC curves at their respective minimum points
Answer:
c
Explanation:
The marginal cost curve image has been attached from which we can clearly, indicate that
ATC = average total cost
AFC = average fixed cost
AVC = average variable cost.
From the graph we can indicate that the marginal cost curve
(c) Lies above the AVC curve when the AVC curve slopes downward.
Se suelta un cuerpo desde la azotea de un edificio de 180m de alto. Luego de 3s se lanza verticalmente hacia abajo otro cuerpo. Si ambos llegan simultáneamente al piso, calcular la rapidez con la que fue lanzado el segundo cuerpo (g=10m/s2).
Answer:CcCcccccc
Explanation:
Rfsgqh
A stone of 1 kg is thrown with a velocity of 40 m/s across the frozen surface of a lake and comes to rest after travelling a distance of 50 m. What is the force of friction between the stone and the ice? *
A)16 N
B)-4 N
C)-16 N
Answer:
C)-16 N
Explanation:
concepts used
force = mass* acceleration
equation of motion
[tex]v^2 = u^2 + 2as[/tex]
where v is the final velocity
u is the initial velocity
and s is the distance moved
______________________________________________
Given
mass = 1 kg
initial velocity (u) = 40m/s
final velocity (v) = 0 as stones comes to rest
distance moved by stone (s) = 50m
using [tex]v^2 = u^2 + 2as[/tex]
[tex]0 = 40^2 +2a*50\\=> -1600 = 100a\\=> a = -1600/100 = -16[/tex]
Thus, acceleration is -16 m/s^2
here acceleration is negative as force of friction is opposing the motion.
Force of friction = mass of stone * acceleration of stone
Force of friction = 1*-16 kgm/s^2 = -16N ( kgm/s^2 = 1 N)
Thus, option c -16N is correct choice.
A butterfly is flying around and its velocity(v) as a function of time(t) is given in the graph below where rightwards is the positive velocity direction. What is the butterfly's displacement x from t=2 to 4s? Answer with two significant digits.
Answer: 19 meters.
Explanation:
We want to find the total displacement between t = 2s and t = 4s.
To do it, we can integrate our function, first write our velocity equation.
for t ≤ 3s, we have a linear equation, let's write it:
A linear relationship can be written as:
y = a*t + b
where a is the slope and b is the y-axis intercept.
For a line that passes through the points (x1, y1) and (x2, y2), the slope can be written as:
a = (y2 - y1)/(x2 - x1).
Now we can see that our line passes through the points (1, 0) and (0, -2)
then the slope is:
a = (0 -(-2)/(1 - 0) = 2/1 = 2
and knowing that when t = 0s, v(0s) = -2m/s, then our equation is:
v(t) = (2m/s^2)*t - 2m/s for t ≤ 3s
now, for t ≥3s the equation is constant, v(t) = 4m/s.
then we have
v(t) = (2m/s^2)*t - 2m/s -------if t ≤ 3s
v(t) = 4m/s ----- if t ≥ 3s
Now we integrate over time to get the position:
for t ≤ 3s we have:
p(t) = (1/2)*(2m/s^2)*t^2 - 2m/s*t + C
where C is a constant of integration, as we are calculating the displacement this constant actually does not matter, so we can use C = 0m
p(t) = (1m/s^2)*t^2 - 2m/s*t for t ≤ 3s
and p(3s) = (1m/s^2)*3s^2 - 2m/s*3s = 9m - 6m = 3m is the initial position of the other part of the function.
for t ≥ 3s we have:
p(t) = 4m/s*t + p(3s) = 4m/s*t + 3m
then the position equation is:
p(t) = (1m/s^2)*t^2 - 2m/s*t ---- t ≤ 3s
p(t) = 4m/s*t + 3m --- if t ≥ 3s
Now the displacement will be:
p(4s) - p(2s) where for each time, you need to use the correct function:
p(4s) = 4m/s*4s + 3m = 16m + 3m = 19m
p(2s) = (1m/s^2)*2s^2 - 2m/s*2s = 4m - 4m = 0m
p(4s) - p(2s) = 19m - 0m = 19m
The butterfly displacement x from t=2 to 4s is 19 meters.
What is displacement?The spacing between two specified points is represented by the one-dimensional quantity of displacement (symbolised as d or s), commonly known as length or distance.
The total displacement between t = 2s and t = 4s.
Integrate our function, the velocity equation.
for t ≤ 3s, we have a linear equation, let's write it:
A linear relationship can be written as:
y = a x t + b
where a is the slope and b is the y-axis intercept.
For a line that passes through the points (x1, y1) and (x2, y2), the slope can be written as:
a = (y2 - y1)/(x2 - x1).
The line passes through the points (1, 0) and (0, -2)
The slope is:
a = (0 -(-2)/(1 - 0) = 2/1 = 2
When t = 0s, v(0s) = -2m/s, then our equation is:
v(t) = (2m/s²) x t - 2m/s for t ≤ 3s
now, for t ≥3s the equation is constant, v(t) = 4m/s.
v(t) = (2m/s²) x t - 2m/s -------if t ≤ 3s
v(t) = 4m/s ----- if t ≥ 3s
Now we integrate over time to get the position:
for t ≤ 3s we have:
p(t) = (1/2) x (2m/s²) x t^2 - 2m/s x t + C
where C is a constant of integration, to calculate the displacement this constant actually does not matter,
p(t) = (1m/s²)*t^2 - 2m/s x t for t ≤ 3s
and p(3s) = (1m/s^2) x 3s² - 2m/s x 3s = 9m - 6m = 3m is the initial position of the other part of the function.
for t ≥ 3s we have:
p(t) = 4m/s x t + p(3s) = 4m/s x t + 3m
then the position equation is:
p(t) = (1m/s^2) x t² - 2m/s x t ---- t ≤ 3s
p(t) = 4m/s x t + 3m --- if t ≥ 3s
Now the displacement will be:
p(4s) - p(2s) where for each time, you need to use the correct function:
p(4s) = 4m/s x 4s + 3m = 16m + 3m = 19m
p(2s) = (1m/s²) x 2s²- 2m/s x 2s = 4m - 4m = 0m
p(4s) - p(2s) = 19m - 0m = 19m
Thus, the displacement is 19 m.
To learn more about displacement, refer to the link:
https://brainly.com/question/11934397
#SPJ2
Open the attached image to see the question.
Answer:
option A
Explanation:
STOVE RADIATE ENERGY
A car accelerates at a rate of 3 m/s^2. If its original speed is 8 m/s, how many seconds will it take the car to reach a final speed of 25 m/s?
Answer:
[tex]\Large \boxed{\mathrm{5.67 \ seconds }}[/tex]
Explanation:
[tex]\displaystyle \mathrm{acceleration \ = \ \frac{final \ velocity - initial \ velocity }{elapsed \ time}}[/tex]
[tex]\displaystyle A \ = \ \frac{V_f - V_i }{t}[/tex]
[tex]\displaystyle 3 \ = \ \frac{25 - 8 }{t}[/tex]
[tex]\displaystyle 3 \ = \ \frac{17 }{t}[/tex]
[tex]\displaystyle t \ = \ \frac{17 }{3} \approx 5.67[/tex]
Will mark as BRAINLIEST.... Plz answer the 44. Ques
Answer:
T= 2.66 seconds
Explanation:
Convert 80 km to m, which would be 0.08 m
[tex]t = d \div s[/tex]
[tex]t = 0.08 km\div 108kmph[/tex]
[tex]t = 0.00074074074 \: h[/tex]
[tex]1 \: hour = 3600 \: sec[/tex]
[tex] \frac{1}{3600} \times \frac{0.00074}{x} [/tex]
[tex]0.00074074074h \times 3600s = 2.66s[/tex]
If the s – t graph of a particle is parallel to the t – axis, the speed of the particle is (a) zero (b) constant (c) infinite (d) non-uniform
Answer:
(b) constant
Explanation:
parallel to t - axis means, at all the times, the s component does not change, it remains same, i. e., the speed is constant.
:-)
Answer:
zero
Explanation:
if the velocity time graph is parallel to the time axis its mean body has not covered the path in other words body is at rest.So the velocity of the body should be zero
so the speed is zero
hope my answer will help u
Earth orbits 1 AU from the Sun, and the Oort cloud extends from about 10,000 to 100,000 AU from the Sun. If you represent Earth’s orbit around the Sun with a paper plate 4 inches in radius, how far away will the inner edge of the Oort Cloud be? The outer edge? Express your answers in miles.
Explanation:
Earth’s orbit around the Sun represented as :
1 AU = 4 inches
Therefore,
Inner edge of the Oort Cloud represented as :
10,000 AU = 40,000 / 63360 = 0.631 miles
Outer edge of the Oort Cloud represented as:
100,000 AU = 400,000 / 63360 = 6.31 miles
Which is
easier
Push
or pull.
when force is at angle
Answer:
pull
Explanation:
because when you push there is one component of force that adds to tge weight of body and hence there is more friction. Whwn you pull the vertical component of force is against the weight of body and hence friction is low.
The motion of a particle along a straight line is described by the equation x=6+4t2 -t 4 , where x is in meter and t is in seconds. Find position, velocity, and acceleration of the object when t=2s.
Answer:
The position of the particle is 6m
The velocity of the particle is 16 m/s in negative direction
The acceleration of the object is -40 m/s²
Explanation:
Given;
motion of the particle along a straight line as x = 6 + 4t² - t⁴
The position of the object when t = 2s
x = 6 + 4(2)² - (2)⁴
x = 6 + 16 - 16
x = 6m
The velocity of the object when t = 2s
Velocity = dx/dt
dx/dt = 8t - 4t³
when t = 2s
Velocity = 8(2) - 4(2)³
Velocity = 16 - 32
Velocity = -16m/s
Velocity = 16 m/s (in negative direction)
The acceleration of the object when t = 2s
Acceleration = d²x/dt² = 8 - 12t²
Acceleration = 8 - 12 (2)²
Acceleration = -40 m/s²
The energy change in an endothermic reaction is: A. Internal B. External C. Negative D. Positive
Answer:
Positive
Explanation:
In an endothermic reaction, the products are at a higher energy than the reactants. This means that the enthalpy change of the reaction (∆H) is positive
A box with mass of 2 kg is pushed directly horizontally over a horizontal surface (with friction) at a constant speed of 10 m/s. The force of the push is 60 N. How much thermal energy is generated pushing the box a distance of 15 m
Answer:
E= 600 W
Explanation:
Given that
m = 2 kg
Speed , v= 10 m/s
Force , F= 60 N
Given that box is moving with constant velocity, it means that friction force will be 60 N.
f = 60 N
Therefore total energy generated
E= f x v
E= 60 x 10 = 600 W
E= 600 W
Thus the answer will be 600 W.
A wave has a frequency of 5 Hz and a wavelength of 0.5 m, what is the speed of this wave?
Answer:
2.5 m/s
Explanation:
The speed of a wave can be found using the following formula.
v= λ * f
where λ is the wavelength in meters (m) and f is the frequency of the wave in Hertz (Hz).
We know the wavelength is 0.5 m and the frequency of the wave is 5 Hz.
Therefore,
λ= 0.5 m
f = 5 Hz
v= 0.5 * 5
Multiply 0.5 by 5, or divide 5 by 2.
0.5 * 5= 2.5 or 5/2=2.5
v= 2.5
Add appropriate units. The units for wave speed are m/s (meters per second).
v= 2.5 m/s
The speed of the wave is 2.5 meters per second.
(8.86 + 1.0 x 10^-3)÷3.610×10^-3
Answer:
2454.57
Explanation:
Step 1: Solve
[tex]\frac{(8.86+0.001)}{(3.610)(10^{-3}) }[/tex]
[tex]\frac{8.861}{0.003.61 }[/tex]
2454.57
Therefor the answer to this equation is 2454.57
Please answer, it's really urgent A boy performs an experiment to measure the speed of sound. He stands 100 meters away form a large wall and claps his hands to make an echo. He claps again as soon as he was the echo, He does this ten times, each time clapping an soon as he hears the echo. The time between the first clap and the tenth echo a recorded. Why it better to time ten echoes together rather than just one echo?
Answer:
Explanation:
The speed of sound is very high . It is about 340 m /s . In one echo , it takes approximately
2 x 100 / 340
= .6 sec
In 10 simultaneous echo , it will take 6 s . It is difficult to measure .6 sec but to measure 6 s is easy and it can be made with greater precision , so we can calculate velocity of sound with great precision .
This is the reason why , instead of one echo , 10 echos are made and duration of 10 echo is measured , rather than making one echo and measuring time of one echo .
How much work is done in moving a body of mass 1.0 kg from an elevation of 2 m to
an elevation of
Answer:
The work done is -176.4 J.
Explanation:
Given that,
Mass = 1.0 kg
An elevation of 2 m to an elevation of 20 m.
Suppose, Find the work done by the gravitational field of the earth?
We need to calculate the force
Using formula of force
[tex]F=mg[/tex]
Put the value into the formula
[tex]F=1.0\times9.8[/tex]
[tex]F=9.8\ N[/tex]
We need to calculate the displacement
Using formula of displacement
[tex]Displacement = s_{2}-s_{1}[/tex]
[tex]s=20-2=18\ m[/tex]
The direction of displacement is upward.
Since gravitational force is downwards and displacement is upwards,
Then the angle is 180°.
We need to calculate the work done
Using formula of work
[tex]W=f\cdos s\cos\theta[/tex]
[tex]W=9.8\times18\cos180[/tex]
[tex]W=-176.4\ J[/tex]
Hence, The work done is -176.4 J.
Identify the wood turning equipment and what it does.
А
is used to turn wood. It rotates and carves wood to produce a
form.
Answer:
lathe
perfectly symmetrical
Answer: A lathe is used to turn wood . It rotates and carves wood to produce a perfectly symmetrical form .
First one is lathe .
Second one is perfectly symmetrical .
Explanation: I just took the test on Plato and had 100%
A machine can never be 100% efficient because some work is always lost due to which factor? friction gravity static input force
Explanation:
Hi,
The answer is friction.
There is almost no machine which are not affected by friction. It losts some work due to friction while working.
Hope it helps..
Answer:
friction
Explanation:
the other options dont effect efficiency
Use the diagram to answer each question.
Why might a researcher further classify the data in the chimpanzee dier table to include separate information of males and females ?
Answer:
In the data table, we can see the frequency distribution in the diet of a given type of chimpanzee.
Why a researcher further classify the data separating information of males and females?
Well, the objective of the researcher is to find information about these chimpanzees, so if he notices that the diet varies (even slightly) between males and females, separating the information between males and females would be useful to know how the diet varies, and why this happens.
This is the primary motive of why a researcher would want to separate the information of males and females.
A 2.00 m long string transmits
waves at 12.9 m/s. At what
frequency will it create standing
waves with 3 loops?
(Unit = Hz)
Answer:
The frequency at which the string will create a standing wave be with three loops is 8.6 Hz
Explanation:
The speed of the of the wave, v = 12.9 m/s
The number of loops of the standing wave = 3 loops
The length of the string = 2.00 m
Given that one loo = half of the wavelength, we have;
Three loops = 3 × half = One and half wavelength = 1.5·λ
The frequency of a wave = f = v/λ
Therefore, we have;
The frequency, f = 12.9/1.5 = 8.6 Hz
The frequency at which the string will create a standing wave be with three loops = 8.6 Hz.
Answer:
9.675
Explanation:
got it right on acellus
[tex]r=s^2/t^2[/tex] 1. If s is tripled and t stays constant, r is multiplied by... 2. If t is doubled, and s stays constant, r is multiplies by...
Answer:
9 and 4
Explanation:
The relation is:
● r = s^2 / t^2
Triplind s means multiplying it by 3. Since it's an equation we should multiply both sides by the same number
Let k be the number we should multiply by r
●k* r = (3s)^2 / t^2
●k* r = 9s^2 /t^2
We have multiplied s^2 by 9 so we should do the same for r.
k = 9
■■■■■■■■■■■■■■■■■■■■■■■■■■
Doubling t means multiplying it by 2.
Let x be the number we shoukd multiply by r.
● x* r = s^2/(2t)^2
● x*r = s^2/ 4t^2
We have multiplied t^2 by 4 so we should do the same for r.
x= 4
(02.10 LC)
Which American sport stems from a combination of the British sports rugby and soccer?
Baseball
Basketball
Tennis
Football
Question 2 Multiple Choice Worth 5 points)
Answer:
football
Explanation:
I took the 2.10 quiz and got it wrong so it must be football
Pls help A car starts from rest and gains a velocity of 20m/s in 10 seconds calculate its acceleration and the distance covered by it in this time
Answer:
[tex] \boxed{\sf Acceleration \ (a) = 2 \ m/s^{2}} [/tex]
[tex] \boxed{\sf Distance \ covered \ (s) = 100 \ m} [/tex]
Given:
Initial velocity (u) = 0 m/s
Final velocity (v) = 20 m/s
Time taken (t) = 10 sec
To Find:
(i) Acceleration (a)
(ii) Distance covered (s)
Explanation:
[tex]\sf (i) \ From \ 1^{st} \ equation \ of \ motion:[/tex]
[tex] \sf \implies v = u + at[/tex]
[tex] \sf \implies 20 = 0 + a(10)[/tex]
[tex] \sf \implies 10a = 20[/tex]
[tex] \sf \implies \frac{10a}{10} = \frac{20}{10} [/tex]
[tex] \sf \implies a = 2 \: m/ {s}^{2} [/tex]
[tex]\sf (ii) \ From \ 2^{nd} \ equation \ of \ motion:[/tex]
[tex] \sf \implies s = ut + \frac{1}{2} a {t}^{2} [/tex]
[tex]\sf \implies s = (0)(10) + \frac{1}{2} \times 2 \times {(10)}^{2} [/tex]
[tex]\sf \implies s = \frac{1}{ \cancel{2}} \times \cancel{2} \times {(10)}^{2} [/tex]
[tex]\sf \implies s = {10}^{2} [/tex]
[tex]\sf \implies s = 100 \: m[/tex]
plz help
I need it fast
Answer:
perpendicular to
Explanation:
it means perpendicular to .....should u come across something like this / / , this one means parallel to .....
Answer:
perpendicular
Explanation:
Some of the most popular symbols are:
Heart symbol: this represents love, compassion and health.
Dove symbol: this represents peace, love, and calm.
Raven symbol: this represents death and doom.
Tree symbol: this represents growth, nature, stability, and eternal life.
Owl symbol: this represents wisdom and intelligence.
If you look at faint stars, you can see them more easily on the edges of your vision than if you try to look directly at them. Why is this true?
Answer:
The retina comprises of rod and cone cells . The rod cells are responsible for black and white vision and require low light levels while the cone cells are responsible for color vision and require good/high light levels for better functioning.
When faint stars are looked at on the edges of the vision it allows more light from faint objects to strike the rod cells which then becomes more visible.
If a gas and a liquid are both at the same temperature, the particles of gas have a higher average kinetic energy. True or false?
Answer:
True
Explanation:
The average kinetic energy is the measure of how freely the molecules of a substance moves relative to the other molecules within the substance. Gas and liquids are together termed fluids, but the molecules of a gas naturally has more more average kinetic energy that that of a liquid, if they are kept at the same temperature. This explains why gases are easy to expand, and have to be confined by a container. So the particles of a gas has more kinetic energy that that of a liquid even if they are kept at the same temperature.
a ferris wheel has a centripetal acceleration equal to 2m/s squared. what is the centripetal force acting on a 45 kg boy riding in one of the cars when the car is on the top of the ferris wheel? what is the force exerted by the seat on the boy when the car is at the top of the ferris wheel
Explanation:
[tex]centripetal \: force = \frac{m {v}^{2} }{r} [/tex]
Centripetal force = 45 * 2 = 90 N
Therefore, centripetal force acting on a 45 kg boy riding in one of the cars when the car is on the top of the ferris wheel is 90 N.
The force exerted by the seat on the boy when the car is at the top of the ferris wheel is a centrifugal (pseudo force) acting (since the since the seat is in non- inertial frame) in exact opposite direction (Outwards) as the centripetal force and is equal in magnitude.
