Answer:
[tex]56.5\ \text{s}[/tex]
[tex]21.13\ \text{m/s}[/tex]
Explanation:
v = Final velocity
u = Initial velocity
a = Acceleration
t = Time
s = Displacement
Here the kinematic equations of motion are used
[tex]v=u+at\\\Rightarrow t=\dfrac{v-u}{a}\\\Rightarrow t=\dfrac{25-0}{2}\\\Rightarrow t=12.5\ \text{s}[/tex]
Time the car is at constant velocity is 39 s
Time the car is decelerating is 5 s
Total time the car is in motion is [tex]12.5+39+5=56.5\ \text{s}[/tex]
Distance traveled
[tex]v^2-u^2=2as\\\Rightarrow s=\dfrac{v^2-u^2}{2a}\\\Rightarrow s=\dfrac{25^2-0}{2\times 2}\\\Rightarrow s=156.25\ \text{m}[/tex]
[tex]s=vt\\\Rightarrow s=25\times 39\\\Rightarrow s=975\ \text{m}[/tex]
[tex]v=u+at\\\Rightarrow a=\dfrac{v-u}{t}\\\Rightarrow a=\dfrac{0-25}{5}\\\Rightarrow a=-5\ \text{m/s}^2[/tex]
[tex]s=\dfrac{v^2-u^2}{2a}\\\Rightarrow s=\dfrac{0-25^2}{2\times -5}\\\Rightarrow s=62.5\ \text{m}[/tex]
The total displacement of the car is [tex]156.25+975+62.5=1193.75\ \text{m}[/tex]
Average velocity is given by
[tex]\dfrac{\text{Total displacement}}{\text{Total time}}=\dfrac{1193.75}{56.5}=21.13\ \text{m/s}[/tex]
The average velocity of the car is [tex]21.13\ \text{m/s}[/tex].
Biodiversity decline poses a problem in an ecosystem because
Answer:
Biodiversity decline continues due to a rapidly expanding human population. Habitat is damaged in order to meet growing needs for agriculture, urban development, water and materials. Fish, wildlife and plants are overharvested, despite mounting evidence that many harvesting practices are unsustainable.
Pedro is planning to model how changes in weather affect evaporation from lakes for his first experiment he wants to test how humidity affects the evaporation rate. he places one beaker with 300 mL of water in a dry area. and places another beaker with 300 mL of water near a humidifier which of the following variables does Pedro need to control during his experiment
A. humidity only
B. humidity and evaporation rate
C. volume of water and tempature
D. volume of water only
Pedro needs to control the variables such as volume of water and temperature during his experiment. So, option C.
What is meant by humidity ?The amount of water vapor in the air is known as humidity. The humidity will be high if there is a lot of water vapour in the atmosphere.
Water can evaporate even at very low temperatures, but as the temperature rises, the rate of evaporation increases.
More surface molecules per unit of volume may be able to escape from a substance with a larger surface area, so it will evaporate more quickly.
The control variables in an experiment are the variables that the experimenter intends to keep constant always so as to limit their effect on the measurements of the relationship between the dependent and the independent variable.
Therefore, in order to have a proper measurement of the effect of humidity on evaporation rate, other variables such as temperature, and the volume of the water in the experiment investigations which affect evaporation rate by the provision of heat, (temperature) and their heat capacity, the volume, etc. should be controlled.
Hence,
Pedro needs to control the variables such as volume of water and temperature during his experiment. So, option C.
To learn more about humidity, click:
https://brainly.com/question/22069910
#SPJ7
The velocity of a particle is given by v=25t2 -80t-200, where velocity is meter per second and time is seconds. Determine the velocity for the first six seconds when acceleration is zero.
Answer:
v = 220 m / s
Explanation:
This is a kinematics exercise, the expression for velocity is
v = 25 t² - 80 t - 200
asks the velocity for time t = 6 s.
let's calculate
v = 25 6² - 80 6 - 200
v = 220 m / s
The velocity for the first six seconds when acceleration is zero is -44 m/s.
What is velocity?
The velocity of an object is the rate of change displacement with time.
The velocity of the object for the first six seconds when the acceleration is zero is calculated as follows;
[tex]a = \frac{dv}{dt} \\\\a = 50t - 80\\\\0 = 50t - 80\\\\50t = 80\\\\t = 1.6 \ s[/tex]
Velocity when time = 1.6 s
[tex]v(1.6) = 25(1.6)^2 - 80(1.6) - 200\\\\v(1.6) = -264 \ m/s[/tex]
The velocity for the first six seconds when acceleration is zero.
[tex]v = v_{a =0} + v_6\\\\v = - 264 \ + 25(6)^2 - 80(6) - 200\\\\v = -44 \ m/s[/tex]
Learn more about velocity here: https://brainly.com/question/6504879
Plz help w answer 1:/ confused ash
Answer:
I would say d I had the same question yesterday and I got it correct so hope that helps
two 0.5 kg carts, one red and one green, sit about half a meter apart on a low friction track, you push on the red one with the constant force of 4N for 0.17m and then remove your hand. the cart moves 0.33 m on the track and then strikes the green cart. what is the work done by you on the two cart system?
Answer:
The work done by you on the two cart system is 2 N-m
Explanation:
Work done is the product of force and displacement.
W = F * D
Substituting the given values we get -
W =
[tex]4 * (0.17+0.33)\\= 2[/tex]
The work done by you on the two cart system is 2 N-m
Determine how would the frequency of the pendulum change if it was taken to the moon by finding the ratio of its frequency on the moon fM to its frequency on the earth fE. Suppose that gE is the free-fall acceleration on the earth and gM is the free-fall acceleration on the moon.
Express your answer in terms of some or all of the variables l, m, gE, gM.
fM/fE = ?
For the pendulum taken to the moon, The frequency change that would occur is mathematically given as
[tex]\frac{Fmoon}{Fearth}=0.408[/tex]
What frequency change would occur to the pendulum if it was taken to the moon?Generally, the equation for the Time period is mathematically given as
[tex]T=2\pi\sqrt{L/g}[/tex]
Therefore
[tex]\frac{Fmoon}{Fearth}=\frac{\sqrt{g/6L}}{\sqrt{g/6L}}\\\\\frac{Fmoon}{Fearth}=\sqrt{1/6}[/tex]
[tex]\frac{Fmoon}{Fearth}=0.408[/tex]
In conclusion, The frequency change
[tex]\frac{Fmoon}{Fearth}=0.408[/tex]
Read more about frequency
https://brainly.com/question/24623209
Answer:
.408
Explanation:
g 2. In a laboratory experiment on standing waves a string 3.0 ft long is attached to the prong of an electrically driven tuning fork which vibrates perpendicular to the length of the string at a frequency of 60 Hz. The weight (not mass) of the string is 0.096 lb. a) [5 pts] What tension must the string be under (weights are attached to the other end) if it is to vibrate in four loops
Answer:
The tension in string will be "3.62 N".
Explanation:
The given values are:
Length of string:
l = 3 ft
or,
= 0.9144 m
frequency,
f = 60 Hz
Weight,
= 0.096 lb
or,
= 0.0435 kgm/s²
Now,
The mass will be:
= [tex]\frac{0.0435}{9.8}[/tex]
= [tex]0.0044 \ kg[/tex]
As we know,
⇒ [tex]\lambda=\frac{2L}{n}[/tex]
On substituting the values, we get
⇒ [tex]=\frac{2\times 0.9144}{4}[/tex]
⇒ [tex]=0.4572 \ m[/tex]
or,
⇒ [tex]v=f \lambda[/tex]
⇒ [tex]=0.4572\times 60[/tex]
⇒ [tex]=27.432 \ m/s[/tex]
Now,
⇒ [tex]v=\sqrt{\frac{T}{\mu} }[/tex]
or,
⇒ [tex]T=\frac{m}{l}\times v^2[/tex]
On putting the above given values, we get
⇒ [tex]=\frac{0.0044}{0.9144}\times (27.432)^2[/tex]
⇒ [tex]=\frac{752.51\times 0.0044}{0.9144}[/tex]
⇒ [tex]=3.62 \ N[/tex]
Which diagram shows magnets that will attract each other? 2 bar magnets side by side with their long axes vertical, both red S on top and blue N on bottom. 2 bar magnets top to bottom with their long axes vertical, the top one with red S on top and blue N on bottom and the bottom magnet with blue N on top and red S on bottom. 2 bar magnets top to bottom with their long axes vertical, the top one with blue N on top and red S on bottom and the bottom magnet with red S on top and blue N on bottom. 2 bar magnets top to bottom with their long axes vertical, the top one with red S on top and blue N on bottom and the bottom magnet with red S on top and blue N on bottom.
2 bar magnets top to bottom with their long axes vertical, the top one with red S on top and blue N on bottom and the bottom magnet with red S on top and blue N on bottom. this diagram shows magnets that will attract each other. Hence option D is correct.
What is Magnet ?A permanent magnet is an item constructed of magnetised material that generates its own persistent magnetic field. A refrigerator magnet, for example, is commonly used to hold notes on a refrigerator door. Ferromagnetic (or ferrimagnetic) materials are those that can be magnetised and are strongly attracted to a magnet. These include the elements iron, nickel, and cobalt, as well as their alloys, some rare-earth metal alloys, and naturally occurring minerals such as lodestone. Although ferromagnetic (and ferrimagnetic) materials are the only ones that are strongly attracted to a magnet and are widely thought to be magnetic, all other substances respond weakly to a magnetic field via one of many different forms of magnetism.
Hence option D is correct.
To know more about magnet :
https://brainly.com/question/21974887
#SPJ3.
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.
Learn more about light waves here:
https://brainly.com/question/23460034
#SPJ6
A spring is hung from the ceiling. When a coffee mug is attached to its end, it stretches 2.5 cm before reaching its new equilibrium length. The block is then pulled down slightly and released. What is the frequency of oscillation
Answer:
Explanation:
In equilibrium , weight of mug is equal to restoring force .
mg = kx where m is mass of mug , k is spring constant and x is extension .
k / m = g / x = 9.8 ms⁻² / .025 m
= 392
frequency of oscillation n = [tex]\frac{1}{2\pi}\sqrt{\frac{k}{m} }[/tex]
[tex]n=\frac{1}{2\pi}\sqrt{392 }[/tex]
= 4.46 per second.
Place the balloon in a bell jar. If available also add some shaving cream and fresh marshmallows. Ask the instructor for help if you are unfamiliar with this apparatus. The motor of the vacuum pump will remove air from the bell jar when it is turned on. Make a prediction about what you think will happen to the balloon as air is removed from the bell jar.
Answer:
The balloon will collapse
Explanation:
When air is removed from the bell jar, the balloon will collapse if the internal pressure from the balloon does not balance the atmospheric pressure from the surroundings.
¿Cuál es la frecuencia de rotación en la tierra?
Answer:
frequency is approximately 11.5 µHz, or more exactly, 11.5740740e-6 Hz
Explanation:
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:
Which term refers to how often a person works out?
Answer: Frequency
Explanation: Frequency is term which best describes how often a person exercises.
Answer:
frequency
Explanation:
I took the. test
⦁ Light coming from a fish makes an incidence angle of 30° to normal under the water. The index of refraction of water is 1.33. A fisherman is looking at the fish through air. At what angle with the normal will the fish appear to the fisherman? Use Snell’s law: .
Answer:
snell's law = sinI /sin r
refractive index = sinI /sin r
1.33= 30 /sinR
sinR= 1.33×30
sinR=39.9
The angle with the normal by which the fish appear to the fisherman is 41.68 degrees.
What is Snell's law?According to the Snell's law, the ratio of index of reflection of the different material is equal to the ratio of incident sine angle and reflective sine angle. It can be given as,
[tex]\dfrac{n_1}{n_2}=\dfrac{\sin\theta_2}{\sin\theta_1}[/tex]
Here (n₁ and n₂) are the index and reflective index and (θ₁ and θ₂) are the incident and reflected angle.
Light coming from a fish makes an incidence angle of 30° to normal under the water. The index of refraction of water is 1.33. A fisherman is looking at the fish through air.The index of refraction of air is 1. Thus, by the Snell's law,
[tex]\dfrac{1}{1.33}=\dfrac{\sin(30)}{\sin\theta_1}\\\theta_1=41.68^o[/tex]
Thus, the angle with the normal by which the fish appear to the fisherman is 41.68 degrees.
Learn more about the Snell's law here;
https://brainly.com/question/10112549
An electron is accelerated through 1.90 103 V from rest and then enters a uniform 1.80-T magnetic field.
(a) What is the maximum magnitude of the magnetic force this particle can experience?
Answer:
https://www.slader.com/discussion/question/an-electron-is-accelerated-through-240-times-103-v-from-rest-and-then-enters-a-uniform-170-t-magnetic-field-what-are-a-the-maximum-and-b-the-9e425fbd/
( Here is solution)
A student wants to determine the speed of sound at an elevation of one mile. To do this the student performs an experiment to determine the resonance frequencies of a tube that is closed at one end. The student takes measurements every day for a week and gets different results on different days. Which of the following experiments would help the student determine the reason for the different results?
a. Repeating the experiment on several 10 degree C days and several 20 degree C days
b. Repeating the experiment using a wider range of frequencies of sound
c. Repeating the original experiment for an additional week
d. Repeating the experiment using a longer tube
Answer:
The correct answer is a
Explanation:
The speed of a sound wave depends on the square root of the modulus of compressibility and the density of the medium.
For the same medium, the speed of sound depends on the temperature of the fora
v = [tex]v_o \ \sqrt{1 + \frac{T}{273} }[/tex]
Therefore, the different results that are obtained are due to changes in temperature. The correct answer is a
since this way it has the values of the speed of sound for each temperature, for which it can compare with the results obtained from the trip.
what type of signal is utilized by the GP's satellite ?
Answer:
Hi how are you doing today Jasmine
Answer:
The answer is B
Explanation:
I did the USA test prep
A record is spinning on a turntable. A record is a uniform disk of mass 1.00 kg and a radius of 0.13 m that spins around an axis through its center. The record is initially spinning at 10 rad/s. Then the motor is turned off and the record slows to a stop with constant angular acceleration. As the record is slowing down it spins through 6.37 revolutions. What is the magnitude of the net torque acting on the record as it slows down
Answer:
T = 0.01 Nm
Explanation:
First, we will calculate the angular acceleration of the disk:
[tex]2\theta\alpha = \omega_f^2-\omega_i^2[/tex]
where,
θ = angular displacement = (6.37 rev)(2π rad/1 rev) = 40.02 rad/s
α = angular acceleration = ?
ωi = initial angular speed = 10 rad/s
ωf = final angular speed = 0 rad/s
Therefore,
[tex](2)(40.02\ rad/s)\alpha = (0\ rad/s)^2-(10\ rad/s)^2[/tex]
α = -1.25 rad/s²
negative sign shows deceleration
α = 1.25 rad/s²
Now, we will calculate the moment of inertia of disk:
[tex]I = \frac{1}{2}mr^2[/tex]
where,
I = Moment of Inertia = ?
m = mass of disk = 1 kg
r = radius of disk = 0.13 m
Therefore,
[tex]I = \frac{1}{2} (1\ kg)(0.13\ m)^2[/tex]
I = 0.00845 kg.m²
Now, the torque can be given as:
T = Iα
T = (0.00845 kg.m²)(1.25 rad/s²)
T = 0.01 Nm
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 playground merry-go-round has a mass of 120 kg and a radius of 1.80 m and it is rotating with an angular velocity of 0.400 rev/s. What is its angular velocity (in rev/s) after a 22.0 kg child gets onto it by grabbing its outer edge
Answer:
The final angular velocity is rev/s is 0.293 rev/s.
Explanation:
Given;
mass of the merry-go-round, m₁ = 120 kg
radius of the merry-go-round, r = 1.8 m
initial angular velocity, ω = 0.4 rev/s
mass of the child, m₂ = 22 kg
Apply the principle of conservation angular momentum to determine the final angular velocity;
[tex]I_i= I_f\\\\\frac{1}{2} m_1r^2 \omega _i = \frac{1}{2} m_1r^2 \omega _f + m_2r^2 \omega _f\\\\ \frac{1}{2} m_1r^2 \omega _i =( \frac{1}{2} m_1r^2 + m_2r^2 )\omega _f\\\\\omega _f = \frac{ \frac{1}{2} m_1r^2 \omega _i}{\frac{1}{2} m_1r^2 + m_2r^2} \\\\\omega _f = \frac{ \frac{1}{2} m_1 \omega _i}{\frac{1}{2} m_1 + m_2}\\\\\omega _f = \frac{0.5 \ \times \ 120\ kg \ \times \ 0.4\ rev/s}{0.5 \ \times 120\ kg \ \ + \ \ 22 \ kg} \\\\\omega _f = 0.293 \ rev/s\\[/tex]
Therefore, the final angular velocity is rev/s is 0.293 rev/s.
the density of brick is 1,600 kg/m3. what is the mass of a brick with a volume of 0.0006 m3? WILL MARK BRAINLIEST
Answer:
.0000004
Explanation:
The mass of a brick with a volume of 0.0006 m³ and a density of 1600 kg/m³ is 0.96kg.
HOW TO CALCULATE MASS?The mass of a substance can be calculated by multiplying the density of the substance by its volume. That is;
Mass = density × volume
According to this question, the density of brick is 1,600 kg/m3 and it has a volume of 0.0006m³. The mass is calculated as follows:
Mass = 0.0006 × 1600
Mass = 0.96kg
Therefore, the mass of a brick with a volume of 0.0006m³ and a density of 1600 kg/m³ is 0.96kg.
Learn more about mass at: https://brainly.com/question/19694949
What is the answer to this problem
Answer:
Material that allow the electrons to move freely in order to produce a current
Please mark as brainliest if answer is right
Have a great day, be safe and healthy
Thank u
XD
What does Binding Energy in the nucleus represent?
Answer:
Nuclear binding energy is the energy required to split a nucleus of an atom into its component parts: protons and neutrons, or, collectively, the nucleons. The binding energy of nuclei is always a positive number, since all nuclei require net energy to separate them into individual protons and neutrons.
I hope you find this helpful.
A woman is driving her car due east at a velocity of 10 m/s. If the woman has a mass of 50 kg and her car has a mass of 1.000 kg, what is the magnitude of the momentum of the woman and her car?
Answer: 10,500 kg m/s
Explanation: (1,000 + 50)(10)
A bat emits a 40 kHz chirp to locate flying insects. If the speed of sound is 340 m/s and a bat hears the echo from the moth after 0.6 seconds, then how far away is the moth?
102 m
Explanation:
The time 0.6 sec is the time it took for the sound to travel from the bat to the moth and back. So it took 0.3 sec for the sound to reach the moth. From the definition of speed, the distance of the moth d to the bat is given by
v = d/t ---> d = vt = (340 m/s)(0.3 sec) = 102 m
Science questions!! Please help!!
Post Assessment on Investigating the Immune System
please help!! Please choose the right answers!! Dont guess if you dont know the answers!!
Convert 125 mL to L
Answer:
1 L = 1000 mL
125 mL = 125/1000 = 0.125 L
Answer:
0.125
Explanation:
divide by 1 000 to convert mL to liters
Two creatures sit on a horizontal frictional rotating platform. The platform rotates at a constant speed. The creatures do not slip off as it rotates.
ASSUME:
Red has a mass of 5 kg
Red is 1.5 m from the center
Red has a speed of 9 m/s
Blue has a mass of 25 kg
Blue has a speed of 1.8 m/s
The force of friction on Red is EQUAL to the force of friction on Blue
DETERMINE:
How far from the center is Blue
Answer:
M v^2 / R = centripetal force
For Red: M v^2 / R = 5 * 9^2 / 1.5 = 270
For Blue M v^2 / R = 270 = 25 * 1.8^2 / Rb
So Rb = 25 * 1.8^2 / 270 = .3 m
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