Answer:
Bus will take 4 seconds before it comes to rest.
Explanation:
Initial Velocity of bus = u = 20 ms⁻¹
Final Velocity of bus = v = 0 ms⁻¹
Deceleration of bus = a = -5 ms⁻²
Time taken by bus before it comes to rest = t = ?
Using the equation formula
a = (v - u)/t
-5 = (0 - 20) / (t)
t = -20/-5
t = 4 sec
Therefore, Bus will take 4 seconds before it comes to rest.
What are some negative impacts of land pollution on humans?
Answer:
Land pollution touches essentially every area of the living world, including: Water that isn't safe to drink. Polluted soil, which leads to a loss of fertile land for agriculture. Climate change, which causes an onslaught of disastrous problems, including flash floods and irregular rainfalls.
Explanation:
HOPE THIS HELPS!!!!!!
Answer:
Look at any ecosystem and there could be multiple forms of contamination—streams full of toxic chemicals from industrial processes, rivers overloaded with nutrients from farms, trash blowing away from landfills, city skies covered in smog. Even landscapes that appear pristine can experience the effects of pollution sources located hundreds or thousands of miles away.
Pollution may muddy landscapes, poison soils and waterways, or kill plants and animals. Humans are also regularly harmed by pollution. Long-term exposure to air pollution, for example, can lead to chronic respiratory disease, lung cancer and other diseases. Toxic chemicals that accumulate in top predators can make some species unsafe to eat. More than one billion people lack access to clean water and 2.4 billion don’t have adequate sanitation, putting them at risk of contracting deadly diseases.
Air pollution brings to mind visions of smokestacks billowing black clouds into the sky, but this pollution comes in many forms. The burning of fossil fuels, in both energy plants and vehicles, releases massive amounts of carbon dioxide into the atmosphere, causing climate change. Industrial processes also emit particulate matter, such as sulfur dioxide, carbon monoxide and other noxious gases. Indoor areas can become polluted by emissions from smoking and cooking. Some of these chemicals, when released into the air, contribute to smog and acid rain. Short term exposure to air pollution can irritate the eyes, nose and throat and cause upper respiratory infections, headaches, nausea and allergic reactions. Long-term exposures can lead to chronic respiratory disease, lung cancer, and heart disease. Long-term exposures also can lead to significant climatic changes that can have far reaching negative impacts on food, water and ecosystems. #SAVE OUR WORLD
pls tell the answer
Just flip one of the batteries to connect one's positive terminal to others negative terminal.
a ray of light parallel to the principal axis of spherical mirror
Answer:
This question is incomplete but the completed question is below
A ray of light parallel to the principal axis of a spherical mirror passes through its _____ after reflection.
(a) focus (b) pole (c) centre of curvature (d) imaginary centre of curvature
The correct option is (a)
Explanation:
After reflection, a ray of light will usually appear to diverge after they hit a spherical mirror, extending behind the mirror to meet at a point (called the focus or focal point) between the pole and the centre of curvature of this mirror. Hence, option a is the correct option.
What do your observations show you about the forces exerted on objects in a collision?
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Help me please I’ll give brainliest
Answer:
zoom in
Explanation:
Please help
4. What are the lowest points on a transverse wave called?
a. Crests
b. troughs
C. compressions
d. rarefractions
5. Any substance that a wave moves through is called a
a. medium
b. vibrate
C. crest
d. frequency
Answer:
Explanation:
the lowest points of a transverse wave are called the troughs what is the wavelength of a wave traveling through a rope if the distance from one crest to the next is 1 meter a. 2 m
4. Low points are called troughs
5. Medium: substance through which a wave can travel
Two forces with magnitudes of 6 pounds and 18 pounds are applied to an object. The magnitude of the resultant is 13 pounds. Find the measurement of the angle between the resultant vector and the vector of the 18 pound force to the nearest whole degree.
Answer: the angle between the resultant vector and the vector of the 18 pound is 28°
Explanation:
given that data in the question; as its interpreted in the diagram below;
from the cosine rule, we know that;
a² = b² + c² - 2bc
so
(13)² = (6)² + (18)² - (2 × 6 × 18 ) cos∅
169 = 36 + 324 - 216cos∅
169 = 360 - 216cos∅
216cos∅ = 360 - 169
216cos∅ = 191
cos∅ = 0.8842
∅ = cos⁻¹ ( 0.8842 )
∅ = 27.8° ≈ 28° {nearest whole number}
Therefore the angle between the resultant vector and the vector of the 18 pound is 28°
A pendulum clock uses a simple pendulum as its timing device. The clock is correct at noon. The next day, when the clock reads noon, the actual time is 11:50 a.m. What is the fractional change in pendulum length that must be made so the clock runs at the correct rate
Answer: the length of the pendulum should be 1.4% longer
Explanation:
Given that;
when its noon, the clock reads 11:50 am,
i.e we have 10 minutes delay ⇒ 10min × 60 = 600secs
we know that in simple pendulum
T = 2π√(l/g)
d means delay and c means correct;
24hrs = 86400 secs
Now
Td/Tc = (86400-600) / 86400 = 0.993 = [2π√(ld/gc)] / [2π√(ld/gc)] = √(ld/lc)
so ld/lc = 0.98616
lc = 1.014 ld
lc/l.d = -1 + 1.014 = 0.014 × 100 = 1.4% longer
therefore the length of the pendulum should be 1.4% longer
A car accelerates at 2 m/s2. Assuming the car starts from rest, how much time does it need to accelerate to a speed of 16 m/s?
Answer:
8 seconds
Explanation:
as per 1st equation of motion
v=u+at,
u= initial velocity, v= final velocity , t=time, a=acceleration
since it starts from rest , u=0
v=16m/s
a=2m/s^2
16=0+2t
16=2t
t=8
9. Who was the FIRST person to propose that the continents might fit together
Answer:
Alfred Wegener
Explanation:
3 women push a stalled car. Each woman pushes with a 425 N force. What is the mass of the car if the car accelerates at 0.85 m/s2?
Answer:
1500kg
Explanation:
Assuming that the women push the car in the same direction, then the total force is:
Fnet = 425 N ⋅ 3
= 1275 N
To find the mass, we use Newton's second law of motion, which states that,
F = ma
where:
·F is the force applied in newtons
·m is the mass of the object in kilograms
·a is the acceleration of the object in meters per second squared.
So we get:
F
m= ⁻⁻⁻⁻⁻
a
1275N
= ⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻
0.85 m/s²
= 1500 kg
What is the kinetic energy of a 1500 kg vehicle traveling at a velocity of 8 m/s?
Answer:
48,000 JExplanation:
The kinetic energy of an object can be found by using the formula
[tex]k = \frac{1}{2} m {v}^{2} \\ [/tex]
m is the mass
v is the velocity
From the question we have
[tex]k = \frac{1}{2} \times 1500 \times {8}^{2} \\ = 750 \times 64[/tex]
We have the final answer as
48,000 JHope this helps you
A block has mass of 20 gm and volume of 4 m3 , calculate the density *
Answer:
Density = 5 g/m³
Explanation:
Given:
Mass of block = 20 gm
Volume of block = 4 m³
Find:
Density
Computation:
Density = Mass / Volume
Density = 20 / 4
Density = 5 g/m³
5 kg/m3
Explanation:
The formula to find density is (d) = mass (m) ÷ volume (v)
Electrical equipment in an office takes a current of 13 A from a 240 V supply.
Estimate the cost per week of electricity if the equipment is used for 30 hours each
week and 1 kWh of energy costs Rm0.50
Answer:
The cost per week of electricity is Rm 46.8
Explanation:
Electrical Power and Energy
The electrical power consumed by an appliance connected to a voltage V and carrying a current I is given by:
P = V.I
The energy consumed by an electrical appliance of power P during a time t is:
E = P.t
The electrical equipment in an office takes I=13 A when connected to a V=240 V supply.
The power consumed is:
P = 240 V * 13 A
P = 3,120 Watt
Converting to Kilowatt:
P = 3,120/1,000 KW
P = 3,12 KW
If the equipment is used t=30 hours each week, the energy is:
E = 3.12 KW * 30 h
E = 93.6 KWh
Since the cost of each KWh is Rm 0.50, the weekly cost of electricity is:
C = 93.6 * 0.50 = 46.8
The cost per week of electricity is Rm 46.8
room's become bright at the day time although there is no bright sunlight in the rooms why
this is give reason
Answer:
The room become bright in the day by a process call scattering of light or Rayleigh scattering.
Explanation:
It is called Rayleigh scattering or scattering of light because Rayleigh scattering is the scattering if light or electromagnetic radiation by smaller particles which have radius of less than 110 nanometer in a medium and the wavelengths of the electromagnetic. Wave or light remain unchanged. The scattering of light occur in the day time in the room and this bring of brighten up of the room.
PLease help i will give brainliest
Answer:
1. False
2. Fats
3. False
Explanation:
MyPlate is an initiative from the United States Department of Agriculture that is designed to help Americans improve their eating habits throughout their lifetimes. Every meal matters. The five food groups represented in My Plate include vegetables, grain, dairy, protein foods, and fruits.
Calories are a source of energy for the human body. So, the more active a person is, the more energy he would need to be supplied to him in form of calories. The less active a person is, the fewer calories he would need.
At a state championship High School football game, the intensity level of the shout of a single person in the stands at the center of the field is 48.1 dB. What would be the intensity level at the center of the field if all 4841 fans at the game shouted from roughly the same distance away from that center point
Answer:
The value is [tex]\beta_f = 84.95 \ dB[/tex]
Explanation:
From the question we are told that
The intensity level of the shout of a single person is [tex]\beta = 48.1 \ dB[/tex]
The number of fans is [tex]n = 4841[/tex]
Gnerally intensity level is mathematically represented as
[tex]\beta = 10 log * \frac{I}{I_o }[/tex]
Here [tex]I_o[/tex] is the minimum intensity of sound human ear can pick and the value is
[tex]I_o = 1 * 10^{-12} \ W/m ^2[/tex]
when [tex]\beta = 48.1 \ dB[/tex]
[tex]48.1 = 10 log * \frac{I}{ 1 * 10^{-12}}[/tex]
=> [tex]4.81 = log ( \frac{ I}{ 1 * 10^{-12}} )[/tex]
taking antilog of both sides
[tex]64565.42 = \frac{I}{ 1 *10^{-12}}[/tex]
=> [tex]I = 6.457 *10^{-8} \ W/m^2[/tex]
Generally the intensity for the whole fans is mathematically represented as
[tex]I_f = n * I[/tex]
=> [tex]I_f = 4841 * 6.457 *10^{-8 }[/tex]
=> [tex]I_f = 0.0003126 \ W/m^2[/tex]
Gnerally the intensity level for the whole fans is mathematically represented as
[tex]\beta_f = 10 log [ \frac{I_f }{I_o } ][/tex]
=> [tex]\beta_f = 10 log [ \frac{ 0.0003126 }{1*10^{-12}}[/tex]
=> [tex]\beta_f = 84.95 \ dB[/tex]
The earth makes one complete revolution around the sun in 365.24 days. Assuming that the orbit of the earth is circular and has a radius of 93,000,000 mi, determine the speedand magnitude of the acceleration of the earth, while treating earth as a point particle.[Hint: you can find the angular speed]Please be consistent with the units.
Answer:
The magnitudes of the speed and acceleration of the Earth are approximately 66,661.217 miles per hour and 47.782 miles per square hour, respectively.
Explanation:
Given that the Earth has a circular orbit and make a revolution at constant speed around the Sun. Then, the kinematic formulas for the speed and acceleration of the planet are, respectively:
Speed
[tex]v = \frac{2\pi\cdot R}{T}[/tex] (1)
Acceleration
[tex]a = \frac{4\pi^{2}\cdot R}{T^{2}}[/tex] (2)
Where:
[tex]v[/tex] - Speed of the planet, measured in miles per hour.
[tex]a[/tex] - Acceleration of the planet, measured in miles per square hour.
[tex]R[/tex] - Radius of the orbit, measured in miles.
[tex]T[/tex] - Period of rotation, measured in hours.
If we know that [tex]R = 93,000,000\,mi[/tex] and [tex]T = 8,765.76\,h[/tex], then the magnitudes of the speed and acceleration of the planet is:
[tex]v = \frac{2\pi\cdot (93,000,000\,mi)}{8,765.76\,h}[/tex]
[tex]v \approx 66,661.217\,\frac{mi}{h}[/tex]
[tex]a = \frac{4\pi^{2}\cdot (93,000,000\,mi)}{(8,765.76\,h)^{2}}[/tex]
[tex]a\approx 47.782\,\frac{mi}{h^{2}}[/tex]
The magnitudes of the speed and acceleration of the Earth are approximately 66,661.217 miles per hour and 47.782 miles per square hour, respectively.
Does anyone know the answer to this page and the next one that it has?
Why do we consider eyes, ears, and fingers as physical sensor
Answer:
because
Explanation:
because we need eye to see if you don't have eyes how you regnise some one
if you have ears how can you know who's voice is who's
if don't have fingers how can you know what your are holding this is why they are called physical sensors
Answer:
because they stimulate our brain and the sensor of human body detect stimuli.
Explanation:
What is the longest wavelength that can be observed in the third order for a transmission grating having 5200 slits/cm?
Answer:
641 nm.
Explanation:
Given that,
A transmission grating has 5200 slits/cm.
We need to find the longest wavelength that can be observed in the third order. Using grating equation as follows :
[tex]d\sin\theta=m\lambda[/tex] ...(1)
d is slit spacing
No fo slit per unit length :
[tex]N={5200}\ slit/cm\\\\=520000\ slits/m[/tex]
We know that, N = 1/d
For longest wavelength, θ = 90°
From equation (1)
[tex]\dfrac{\sin\theta}{m\lambda}=\dfrac{1}{d}\\\\520000=\dfrac{\sin(90)}{3\lambda}\\\\\lambda=\dfrac{1}{520000\times 3}\\\\=6.41\times 10^{-7}\ m\\\\=641\ nm[/tex]
Hence, the longest wavelength in third order for a transmission grating is 641 nm.
I AM 145 LBS. I FELL FROM A TABLE TOP THAT WAS 4.5 FEET HIGH AND LANDED ON MY HAND WHICH WAS TURNED BACKWORDS. I BROKE BOTH MAJOR BONES IN MY ARM DIRECTLY ABOVE MY WRIST. WHAT IS THE FORMULA OF THE FORCE AND WEIGHT HITTING THE FLOOR
The angle between incident ray and reflected ray is 60°. What will be the value of angle of incidence and angle of reflection.?
The angle between incident ray and reflected ray is 60 degree. the value of angle of incidence and angle of reflection is 30 degree
HELP ME NOW PLZ
What is the speed of a boy moving around a circular park of
radius 6 m if he goes once around the park in 20 s?
A-1.88m/s
B-3.76m/s
C-5.65m/s
D-None of the above
Answer: 1.88 m/s
Explanation:
The speed of the boy moving around a circular park of radius 6 m and taking time 20 seconds is 1.88 m/s.
What is speed?Speed is a measurement of how quickly an object's distance traveled changes. Speed is a scalar, which implies it has magnitude but no direction as a unit of measurement.
A thing that moves quickly and with great speed, covering a lot of ground in a short time. On the other hand, a slow-moving object traveling at a low speed covers a comparatively small distance in the same amount of time.
Given information:
The radius of the circular park, r = 6 m,
The time is taken to cover one round, t = 20s,
The total distance covered by the boy is equal to the circumference of the park, so
d = 2[tex]\pi[/tex]r,
[tex]d = 2*3.14*6\\d = 37.68 m[/tex]
Now,
the speed of the boy, s = [tex]37.68/20[/tex] ,
s = 1.88 m/s
Therefore, the speed of the boy moving around a circular park of radius 6 m and taking time 20 seconds is 1.88 m/s.
To know more about speed:
https://brainly.com/question/13074982
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A space probe is sent to an alien planet and conducts an experiment in order to determine the acceleration due to gravity on the planet. It produces the following table
Object Rock Grain of sand Metal bolt
Mass 20 grams 0.8 grams 79 grams
Recorded force of gravity :0.1224 N 0.00501 N 0.4871 N
Given this data, which of the following the closest approximation of the acceleration due to gravity on this planet
a
3.8 m/s^2
b
4.0 m/s^2
c
9.9 m/s^2
d
6.1 m/s^2
Answer: D. 6.1 m/s^2
Explanation:
To understand the meaning of the variables that appear in the equations for rotational kinematics with constant angular acceleration. Rotational motion with a constant nonzero acceleration is not uncommon in the world around us. For instance, many machines have spinning parts. When the machine is turned on or off, the spinning parts tend to change the rate of their rotation with virtually constant angular acceleration. Many introductory problems in rotational kinematics involve motion of a particle with constant, nonzero angular acceleration. The kinematic equations for such motion can be written as
Answer:
ω = ω₀ + α t
ω² = ω₀² + 2 α θ
θ = θ₀ + ω₀ t + ½ α t²
Explanation:
Rotational kinematics can be treated as equivalent to linear kinematics, for this change the displacement will change to the angular displacement, the velocity to the angular velocity and the acceleration to the angular relation, that is
x → θ
v → ω
a → α
with these changes the three linear kinematics relations change to
ω = ω₀ + α t
ω² = ω₀² + 2 α θ
θ = θ₀ + ω₀ t + ½ α t²
where it should be clarified that to use these equations the angles must be measured in radians
A 50.0-kg child stands at the rim of a merry-go-round of radius 2.00 m, rotating in such a way that it makes one revolution in 2.09 s. What minimum coefficient of static friction between her feet and the floor of the merry-go-round is required to keep her in the circular path
Answer:
2.01
Explanation:
First, we need to find the centripetal acceleration.
We're given that the merry go round rotates 1 revolution in 2.09 seconds. Converting to rpm, we know that it rotates 30 revolution per minute
Now this speed gotten in rpm will be converted to m/s, to ease the calculation
30 rpm = πdN/60 m/s
30 rpm = (3.142 * 4 * 30)/60
30 rpm = 377.04/60
30 rpm = 6.284 m/s
a(c) = v²/r
a(c) = 6.284²/2
a(c) = 39.49 / 2
a(c) = 19.74 m/s²
F = ma
F = 50 * 19.74
F = 987 N
Also, Normal Force, F(n) =
F(n) = mg
F(n) = 50 * 9.81
F(n) = 490.5
We then use this to find the coefficient of static friction, μ
μ = F/F(n)
μ = 987 / 490.5
μ = 2.01
A boy on a bicycle approaches a brick wall as he sounds his horn at a frequency 400 Hz. The sound he hears reflected back from the wall is at a frequency 408 Hz. At what speed is the boy riding his bicycle toward the wall
Answer:
6.8 m/s
Explanation:
To solve this, we would use the Doppler's Effect. Doppler's effect is represented by the formula
f = [(g + vr)/(g + vs)].fo, where
f = observed frequency, 408 Hz
g = speed of sound in air, 340 m/s
vr = velocity of the receiver
vs = velocity of the source, 0 m/s
fo = source frequency, 400 Hz
Now, applying the values to the equation, we have
408 = [(340 + vr)/(340 + 0) * 400
408/400 = (340 + vr)/340
1.02 * 340 = 340 + vr
346.8 = 340 + vr
vr = 346.8 - 340
vr = 6.8 m/s
Therefore the speed at which the boy is riding his bicycle towards the wall is 6.8 m/s
Helping me please What can smart modern biosensors be used in heath applications?
Answer: Biosensors are modern electronic devices which are made up of biological recognition system and a transducer, for processing of signals and to quantify a particular analyte.
Explanation:
In modern medicine, a Biosensors are used to replace some clinical laboratory investigations of biological fluids with the advantages of being easy to use, rapid and robust as well as offering multianalyte testing capability. They are classified based on their biological recognition elements which includes:
--> enzymatic biosensors
--> immuno biosensors
--> DNA and whole cell biosensors.
They can also be classified according to their signal transduction methods. These includes:
--> electrochemical Biosensors,
--> optical biosensors,
--> thermal and mass-based biosensors;
Some of the HEALTH APPLICATIONS of a modern biosensor includes:
--> Monitoring of glucose levels in diabetic patients which makes use of enzyme based sensors to monitor concentration of glucose in patients.
--> Detection of general metabolic status of bacteria, fungi, yeast, animal or plant cells.
--> Monitoring of cholesterol levels to prevent cardiovascular diseases. Cardiac troponin and. C - Reactive Proteins are biomarkers that are easily detected using biosensors.
--> They are used for Cancer clinical testings
10. During 4th period we put Klaudia in a box because she was talking too much. We still heard her voice through the box so we decided to push her outside. The force of friction of the ground on the box was 68 N. If Mr.Whitmore can apply a force of 25 N and every other 7th grade student can apply a force of 6 N. How many students would Mr. Whitmore need to make the box start moving and go outside. (Think quickly, the faster we move the box out, the quicker she stops talking)
Answer: Mr. Whitmore would need 7 or more students ( 7.17) to make the box start moving and go outside
Explanation:
Given that;
friction force of ground box = 68 N
student of 7th grade = n
Whitmore can apply a force of 25 N
every other 7th grade student can apply a force of 6 N.
now
friction force = forced applied by whitmore + total force ny 7th grade student
we substitute
68 = 25 + 6n
6n = 68 - 25
6n = 43
n = 43/6
n = 7.17
Therefore Mr. Whitmore would need 7 or more students ( 7.17) to make the box start moving and go outside
