Answer:
The time it will take for the car to reach a velocity of 28 m/s is 7 seconds
Explanation:
The parameters of the car are;
The acceleration of the car, a = 4 m/s²
The final velocity of the car, v = 28 m/s
The initial velocity of the car, u = 0 m/s (The car starts from rest)
The kinematic equation that can be used for finding (the time) how long it will take for the car to reach a velocity of 28 m/s is given as follows;
v = u + a·t
Where;
v = The final velocity of the car, v = 28 m/s
u = The initial velocity of the car = 0 m/s
a = The acceleration of the car = 4 m/s²
t = =The time it will take for the car to reach a velocity of 28 m/s
Therefore, we get;
t = (v - u)/a
t = (28 m/s - 0 m/s)/(4 m/s²) = 7 s
The time it will take for the car to reach a velocity of 28 m/s, t = 7 seconds.
A uniform beam is balanced at its midpoint. An object is placed on the beam as shown. Which force will rebalance the beam
The image of the uniform beam is missing, so i have attached it.
Answer:
Option D: 90N acting downwards, 20cm to the left of the midpoint
Explanation:
Taking moments about the pivot, for the beam to be balanced, the moments to the left of the pivot must be equal to the moments to the right of the pivot.
Thus, it also means that; anti clockwise moment = clockwise moment.
Now, from the image, the moment of the left force about the pivot is an anti clockwise moment = 60 × 30 = 1800 N.cm
Now, for the beam to be rebalanced, we need a clockwise moment to the right of the pivot that is equal to 1800 N.cm.
Thus, the clockwise moment would have to be gotten from a downward force to the right of the pivot.
From the options given, the only downward force to the right of the pivot that produces a moment equal to 1800 N.cm is;
Option D: 90N acting downwards, 20cm to the left of the midpoint
answer this plsss
A mobile phone operates at 900 MHz.
What wavelength does it use?
Answer:
The wavelength = 0.3333 meters at 900 MHz, therefore, = /4 = 0.08333 meters.
If you are pushing a box toward your friend with a force of 20 N, and your friend is pushing the box toward you with a force of 30 N, what will happen to the box?
Answer : the box will move backwards with a force 10 N
Explanation :
F1 = 20 N
F2 = 30 N
F = F2 - F1 = 30 - 20 = 10 N
Which household item uses radiation in a beneficial way? conventional ovens smoke detectors electric air filters computers and TV sets
Answer:
Smoke detectors
Explanation:
This is because the ionization chamber in smoke detectors uses radiation, a form of heat transfer to detect smoke.
.The NRC allows beneficial use of smoke detectors which is a radioactive material because a smoke detector has the ability to save lives . it's ability to save lives outweighs any health risk from the radiation. The smoke detector use a very minimal amounts of radioactive materials.
Answer: The household item which uses radiation in a beneficial way is the SMOKE DETECTORS
Explanation:
Radiation is a type of energy that has the ability to travel through space and penetrate materials. There are various types of radiation which include alpha, beta and gamma rays. Many uses of radiation help to ensure high quality and safety of our daily lives. A typical example is seen in smoke detectors.
Smoke detectors are devices installed in a building which serves the purpose of detecting smoke which usually is associated with fire and sounding off an alarm. The types of smoke detectors available depends on their mode of action and these include:
--> Ionization smoke detectors: These type of detector are generally more sensitive to flamming fires. They have an in built small amount of RADIOACTIVE material between two electrically charged plates, which ionizes the air and causes current to flow between the plates. When smoke enters the chamber, it disrupts the flow of ions, thus reducing the flow of current and activating the alarm. An isotope of americium which emits alpha particles is used in this type of smoke detectors and it's an example of an alpha radiation.
Therefore, the household item which uses radiation in a beneficial way is the SMOKE DETECTORS.
Si un ciclista se mueve a una velocidad de 5 m/s y acelera 1 m/s2, a los 10 segundos su velocidad será
Answer:
A los 10 segundos su velocidad será 15 [tex]\frac{m}{s}[/tex]
Explanation:
La aceleración de un objeto es una magnitud que indica cómo cambia la velocidad del objeto en una unidad de tiempo.
En otras palabras, la aceleración relaciona los cambios de la velocidad con el tiempo en el que se producen, es decir que mide cómo de rápidos son los cambios de velocidad:
Una aceleración grande significa que la velocidad cambia rápidamente. Una aceleración pequeña significa que la velocidad cambia lentamente. Una aceleración cero significa que la velocidad no cambia.La aceleración "a" puede ser calculada mediante la expresión:
[tex]a=\frac{vfinal - vinicial}{tiempo}[/tex]
En este caso:
a= 1 [tex]\frac{m}{s^{2} }[/tex]vfinal= ?vinicial= 5 [tex]\frac{m}{s}[/tex]tiempo= 10 sReemplazando:
[tex]1\frac{m}{s^{2} }=\frac{vfinal - 5\frac{m}{s} }{10 s}[/tex]
Resolviendo se obtiene:
1 [tex]\frac{m}{s^{2} }[/tex] *10 s= vfinal - 5 [tex]\frac{m}{s}[/tex]
10 [tex]\frac{m}{s}[/tex] = vfinal - 5 [tex]\frac{m}{s}[/tex]
10 [tex]\frac{m}{s}[/tex] + 5 [tex]\frac{m}{s}[/tex] = vfinal
15 [tex]\frac{m}{s}[/tex] = vfinal
A los 10 segundos su velocidad será 15 [tex]\frac{m}{s}[/tex]
A spaceship captain lands on an unknown planet. Before venturing forth, he needs to find out the acceleration due to gravity on that planet. All he has available to him is some thin light string, a stopwatch, and a small 2.75-kg metal ball (it was a rough landing). So he lets the ball swing from a 1.5-m length of the string, starting at rest, and measures that it takes 1.9 s for it to swing from the place where he released it to the place where it first stops as it reverses direction. What is the acceleration due to gravity on this planet
Answer:
g = 4,10 m/s
Explanation:
Este es un ejercicio de péndulo simple, donde la velocidad angular esta dada por
w = [tex]\sqrt{ \frac{g}{L} }[/tex]
la velocidad angular esta relacionada con el periodo
w =2π/T
sustituimos
[tex]\frac{2\pi }{T} = \sqrt{ \frac{g}{L} }[/tex]2pi/T = Ra g/L
T² = [tex]4\pi ^2 \frac{ L}{g}[/tex]
g = [tex]4\pi ^2 \ \frac{L}{T^2}[/tex]
el periodo es el tiempo de una oscilación completa, osea desde el punto donde se suelta hasta que regresa al mismo punto, en este caso tenemos medio periodo, desde donde se suelta hasta donde se detiene
T/2 = 1,9
T = 2 1,9
T = 3,8 s
calculemos
g = 4π² 1,5 /3,8²
g = 4,10 m/s
Using the data above, what would be the independent variable? Type of coke (Diet Coke or Coca Cola) Height of Explosion Trial number or Number of Mentos?
The answer is A. Type of coke (Diet or Coca-Cola) is the correct answer.
(I took the test.)
TTC
The TTC subway train in Toronto starts from rest at the Kipling station and accelerates at a
rate of 4.0 m/s for the first 6.0 s. The train then maintains a constant speed for the next
45.0 s.
(a)
(B)
Calculate the train's velocity after 6.0 s have elapsed.
Determine the displacement of the train after 51.0 s of travel.
a reaction occurs in which carbon combines with sulfur to form carbon disulfide is this a chemical reaction or a nuclear reaction and how do you know
Answer:
a chemical reaction where electrons mix.
Explanation:
A nuclear reaction is when atomic nuclei combine, forming a new chemical element
A chemical reaction occurs when electrons from the last layer of atoms mix, forming molecules that have the same chemical elements as the reactants.
According to these definitions
C + 2 S → CS2
in a chemical reaction where electrons mix.
Answer:
This is a chemical reaction, because only the electrons were rearranged.
A student is creating a model of a concave lens. The diagram shows her incomplete model.
Which action would best complete her model?
A
The student should draw the light moving into the lens and then exiting in converging lines.
B
The student should draw the rays of light moving into the lens and then exiting at right angles.
C
The student should draw the rays of light moving into the lens and then exiting in a straight path.
D
The student should draw the light moving into the lens and then exiting in lines that are spreading out.
Answer:
D
Explanation:
I’m pretty sure it’s correct but I don’t really know. Just trying to pass science
Answer:
The correct answer is D trust me I did the test
When the concave lens moves in it exit by spreading out like water
An airplane is cruising at a speed of 250 m/s. If the airplanes engines provide a forward force of 19,540 N, calculate the force of the air resistance (friction) that is acting on the plane.
Answer:
19,540 N
Explanation:
if you have a force at an angle in order to get it with the horizontal you get the Force times cosine the angle and if you want it with the vertical you got the Force times sine the angle
Light travels at a speed of equation m/s in air. What is the speed of light in glass, which has an index of refraction of 1.5?
Answer:
[tex]2\times 10^{8}\ \text{m/s}[/tex]
Explanation:
[tex]n[/tex] = Refractive index of glass = 1.5
[tex]c[/tex] = Speed of light in vacuum = [tex]3\times 10^8\ \text{m/s}[/tex]
Refractive index is given by
[tex]n=\dfrac{c}{v}\\\Rightarrow v=\dfrac{c}{n}\\\Rightarrow v=\dfrac{3\times 10^8}{1.5}\\\Rightarrow v=2\times 10^{8}\ \text{m/s}[/tex]
The speed of light in the glass is [tex]2\times 10^{8}\ \text{m/s}[/tex].
What is the law of inertia? Give an example of inertia in action.
Answer:
The law of inertia is another name for Newton's first law. Newton's first law states that an object will not change its motion or direction unless a force acts on it. An object at rest will stay at rest and an object in motion will stay in motion if there isn't any force acting on them.
Example: When a car uses its brakes to stop, you sometimes feel like you are sliding forward. That is because the inertia keeps you moving forward, even though the car stopped.
Explanation:
Answer:
Law of inertia is sometimes called Newtons First law of motion.
Newtons first law of motion states that"A body will continue to its state of rest or motion unless external force acted upon it.
Convert 350.0mL at 740 K to its new volume at standard temperature
Answer:
129.12 ml
Explanation:
If answer is correct feel free to replay me for explanation.
What type of local wind would most likely occur in the image below?
mountain breeze
sea breeze
valley breeze
land breeze
The correct answer is sea breeze
Answer:
Land breeze.
Explanation:
The breeze that blows from the land toward the sea after sunset. The land cools more quickly than the ocean, cooling the air above it. The warmer air above the water continues to rise, and cooler air from over the land replaces it, creating a breeze.
1. A body undergoing Uniform motion covered 12.5km with in 2.8 min. Determine:
A. The speed of the body
B. The time to cover 0.5km
C. The distance covered in 12min
what is comma please plz me.!!
Answer:
A comma.....
Explanation:
Looks like this (,), and can be used if you have run-on sentences.
I hope this helps :)
hi
what's up
wrud
hmm
hmm
Match the following moves to the correct total distance and displacement of the moves.
A) Move 12 m west and then 8 m east
B) Move 9 m west and then 16 m east
C) Move 10 m east and then 12 m west
D) Move 5 m east and then 12 m east
1) Displacement is 17 m
east; distance is 17 m
2) Displacement is 2 m west; distance is 22 m
3) Displacement is 7 m east; distance is 25 m
4) Displacement is 4 m west; distance is 20 m
Answer:
A=4
B=3
c=2
D=1
Explanation:
since the person moving in opposite direction so displacement =distance in east/west - distance in west/east
Four satellites are in orbit around the Earth. The heights of their four orbits
are identical. The masses of the four satellites are given in the table. For
which satellite is the gravitational pull of Earth the strongest?
A. Satellite A
B. Satellite B
C. Satellite C
D. Satellite D
The gravitational pull of Earth is stronger in satellite A
. If a train going 60 m/s hits the brakes, and it takes the train 25 seconds to stop, what is the train’s acceleration
1. What would you need to move a soccer ball?
a. Friction
b. Gravity
c. Force
d. Inertia
Answer:
Force
Explanation:
How high (in meters) can a 40 N force move a load, when 395 J of work is done? (round to the nearest 10th)
Answer:
9.9 m
Explanation:
From the question given above, the following data were obtained:
Force (F) = 40 N
Workdone (Wd) = 395 J
Height (h) =?
The height can be obtained as follow:
Potential energy = mgh = Fh
395 = 40 × h
Divide both side by 40
h = 395 / 40
h = 9.9 m
Thus, the height is 9.9 m.
SCIENCE<3:: will give brainliest! :)
Answer:
Option two
Explanation:
im smort
Answer:
I think it's B. there is a cold air mass pushing warm air mass up and replacing it over San Francisco
our ancestors are our guides?
Answer:
yes
Explanation:
we can clearly say that our ancestor are our guide.
Because of they give us different knowledge about evolution of life and etc.
Small pieces of sand hitting the side of a mountain and weathering the rock is an example of what type of weathering?
Answer: This is MECHANICAL type of weathering.
Explanation:
Weathering is defined as the process by which rocks breakdown into smaller quantities due to different atmospheric and biological activities.
There are different types of weathering which include:
--> MECHANICAL WEATHERING: This type of weathering is also called physical weathering. Here, rocks are being broken down into smaller pieces but the mineral composition of the rock remains the same. This type of weathering can occur in two ways:
• By Ice wedging: this is one of the easiest ways rocks can be broken into smaller pieces. It occurs at the earth polar regions (climate that regularly cycles above and below the freezing point) and in areas of higher elevations such as the mountains. Ice wedging of rocks occurs when water seeps into cracks, it freezes and expands. This results in wedging (splitting) the rocks apart with repeated freezing.
• By Abrasion: this is another form in which mechanical weathering occurs. Abrasion occurs when strong winds carrying pieces of sand sandblast mountain surfaces. Also moving water, gravity, biological activities can cause abrasion of rock surfaces leading to its weathering.
Therefore, small pieces of sand hitting the side of a mountain and weathering the rock is an example of mechanical weathering by abrasion.
Match the situation with the energy type.
Answer:
snowplow would be m, sun r , hb n , FB e ,and tiaa c
Mistakes in a DNA sequence is known as
Answer:
mistakes are called. mutations. mutations are. changes in the sequence of DNA. mistakes can be made during the DNA replication process but DNA replication process has features that reduce mutations.
Explanation:
hope this helps
Two swimmers competed in a race. The graph shows how the position of both swimmers
changed over time during the race.
Two swimmers competed in a race. The graph shows how the position of both swimmers
At what rate of speed did Swimmer 1 travel throughout the race?
Answer:
2m/s
Explanation:
Calculate the slope at any point as the line is linear. i.e. 20/10 = 2/1 m/s
El peso normal de un estudiante de secundaria es 725 N y el área de los dos zapatos que usa es de 412 cm2 . La presión medida que sus zapatos ejercen en el suelo es
Answer:
Presión = 175,97 N/m²
Explanation:
Dados los siguientes datos;
Peso del alumno (fuerza) = 725N
Área de zapatos = 412 cm² a metros cuadrados = 412/100 = 4.12 metros
Para encontrar la presión, usaríamos la siguiente fórmula;
Presión = fuerza / área
Presión = 725 / 4.12
Presión = 175,97 N/m²
What role does the sun play in driving the water cycle in Antarctica
Answer:
the inner regions of antarctica gets only about 2 inches of precipitation per year. the winds here blow up snow from the land and put it into the atmosphere, which is part of the water cycle. and the sun helps out, too, causing sublimation to occur, which causes snow to evaporate directly into water vapor gas.
Explanation:
good luck, hope this helps :)
have a nice day !!