Answer:
Explanation:
[tex]a=\frac{v_f-v_0}{t}[/tex] We don't yet need the mass of the car, as we can see by this equation. What we do need is the velocity of the car, the initial velocity, in meters per second, and right now it's in km/hr. Not good. We need to convert. The conversion is as follows:
[tex]54\frac{km}{hr}*\frac{1000m}{1km}*\frac{1hr}{3600s}=15\frac{m}{s}[/tex] Ok, that's good. Now we have everything we need but the time element. If the car traveled a distance of 40 meters at 15 m/s, then we can use the d = rt equation to solve for t, and when we find t we plug it into the acceleration equation:
40 = 15t and
t = 2.7 seconds. The car traveled for 2.7 seconds to go that 40 meters. That's the only reason we were given the displacement. We need it for nothing else but that.
Filling in the acceleration equation now:
[tex]a=\frac{0-15}{2.7}=-5.6\frac{m}{s^2}[/tex] and the negative indicates we are in fact slowing down. That's the answer for the acceleration portion of the problem; now we need the force, F, applied to the brakes.
F = ma where m is mass (we get to use that value now!) and a is -5.6 m/s/s.
F = 500(-5.6) and
F = -2800 N and the negative here means that the force of the brakes is acting against the motion of the car: the brakes are pulling the car "backwards" to stop while the car's motion is forward. The negative indicates the direction the force is being applied.
what is the story of coal
Explanation:
Coal is a fossil fuel and is the altered remains of prehistoric vegetation. The energy we get from coal today comes from the energy that plants absorbed from the sun millions of years ago. In the burning process of coal, carbon dioxide (CO2) is emitted. Humans expel CO2, and plants utilize it every single day. Carbon is a building block for all forms of life and is used in a lot of everyday products.
Coal is a combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams. Coal is mostly carbon with variable amounts of other elements, chiefly hydrogen, sulfur, oxygen, and nitrogen.Coal is formed when dead plant matter decays into peat and is converted into coal by the heat and pressure of deep burial over millions of years. Vast deposits of coal originate in former wetlands—called coal forests—that covered much of the Earth's tropical land areas during the late Carboniferous (Pennsylvanian) and Permian times. However, many significant coal deposits are younger than this and originate from the Mesozoic and Cenozoic eras.
Answer:
look it up of goog le
Explanation:
Si la fuerza de fricción cinetica es 250N ¿Qué fuerza se necesita para mantener a la caja deslizándose a una velocidad constante ¿
Answer:
250N
Explanation:
According to newton second law,
\sumF = ma
Fm - Ff = ma
Since the velocity is constant, a = 0m/s
Frictional force Ff = 250N
Substitute
Fm - 250 = m(0)
Fm - 250 = 0
Fm = 250N
Hence the force to keep the box sliding at constant speed is 250N
which physical property of the gas molecules gives the measurement of temperature
The temperature of a gas molecule is measured by the average translational kinetic energy
Answer:
The temperature of a gas is a measure of the average translational kinetic energy of the molecules. In a hot gas, the molecules move faster than in a cold gas; the mass remains the same, but the kinetic energy, and hence the temperature, is greater because of the increased velocity of the molecules
Explanation:
This is also from Go0gle because my explanation would've been an essay long .
but in shorter version if the gas molecules move fast it's hot an if it moves slow its cold hope this helps .
Write a balanced nuclear reaction for one complete cycle
Answer:
H + H ------> He + energy. He + He -----> H + H + He.
Explanation:
Hydrogen having one proton and no neutron fuse with hydrogen having one proton and one neutron forming helium atom with the release of photon. After that two helium atoms combine together forming two hydrogen atoms having one proton each whereas one helium atom having two protons and two neutrons present in their nucleus so the end product of this reaction is hydrogen atoms and helium.
In nonequilibrium, total counterclockwise moments = total clockwise moments. *True False
Answer:
[tex]{ \bf{false}}[/tex]
Explanation:
Because it breaks the law of moments.
The number of windings on the primary coil of a transformer
is 1.5 times greater than on the secondary coil. The primary
coil has a current of 3.0 A and a voltage of 12.0 V. Determine
the voltage and current on the secondary coil.
Answer:
I. Vs = 8.0 Volts.
II. Is = 4.5 Amperes.
Explanation:
Given the following data;
Np = 1.5Ns = [tex] \frac {N_{P}}{N_{S}} = 1.5 [/tex] ..... equation 1
Ip = 3.0 A
Vp = 12 V
To find the voltage and current on the secondary coil;
I. For the voltage in the secondary coil (Vs), we would use the following formula;
[tex] \frac {V_{P}}{V_{S}} = \frac {N_{P}}{N_{S}} [/tex] ...... equation 2.
Substituting eqn 1 into eqn 2, we have;
[tex] \frac {V_{P}}{V_{S}} = 1.5 [/tex]
[tex] \frac {12}{V_{S}} = 1.5 [/tex]
Cross-multiplying, we have;
[tex] V_{S} * 1.5 = 12 [/tex]
[tex] V_{S} = \frac {12}{1.5} [/tex]
Vs = 8.0 V
II. For the current in the secondary coil (Is), we would use the following formula;
[tex] \frac {I_{S}}{I_{P}} = \frac {N_{P}}{N_{S}} [/tex] .... equation 3
Substituting eqn 1 into eqn 3, we have;
[tex] \frac {I_{S}}{I_{P}} = 1.5 [/tex]
[tex] \frac {I_{S}}{3.0} = 1.5 [/tex]
Cross-multiplying, we have;
[tex] I_{S} = 1.5 * 3.0 [/tex]
Is = 4.5 A
Write the dirference between sl system
and cgs system
Explanation:
st system:the internationak system of measurement which i declared form internationäl convention of scientists held in france in 1960AD is Si system
CGS System:it measure in length in centimeter mass in gram time in second
Please help
25 Points
What Mathematical leads to the formulas for the magnitudes of displacement, velocity, and acceleration?
Answer:
displacement=specific distance
*Velocity=∆displacement/time
*acceleration=∆velocity/time
A. Tick (1) the best alternatives. 1. What is the acceleration due to gravity on the surface of moon ? (a) 9.8m/s (b)1.6m/s2 (c) 6.67x10-1m/s (d) 9.8m/s?
Answer:
[tex] \green{ \sf \: \: 1.6 \: m {s}^{ - 2} \: \: \: is \: the \: correct \: answer}[/tex]
Explanation:
[tex] \sf \: \huge{g } _{ \small{moon}} = \frac{ {\huge{g}}_{earth}}{6} \\ \\ \sf \implies \: \sf \: \huge{g } _{ \small{moon}} = \frac{ 9.8}{6} = 1.6 \: \: m {s}^{ - 2} [/tex]
Un auto se desplaza por una carretera recta a una velocidad de 85 km/h. Al cabo de 2 horas, ¿qué distancia habrá recorrido, en metros?
Answer:
Distancia, D = 170,000 metros
Explanation:
Dados los siguientes datos;
Velocidad = 85 km/h Tiempo = 2 horasPara encontrar la distancia recorrida, en metros;
Matemáticamente, la distancia recorrida por un objeto se calcula mediante la fórmula;
Distancia = velocidad * tiempo
Sustituyendo los valores en la fórmula, tenemos;
Distancia = 85 * 2
Distancia = 170 kilómetros
A continuación, convertiríamos el valor en kilómetros a metros;
Conversión:
1 kilómetros = 1000 metros
170 kilómetros = D metros
Multiplicación cruzada, tenemos;
D = 170 * 1000
D = 170,000 metros
Por lo tanto, habría viajado 170,000 metros después de 2 horas.
(ik it says physics but astronomy is a field of physics sooo) A recently discovered planet in a different solar system is located 1.85 x 10^15 Miles from earth. To the nearest 10th of a light year, how far is this planet from earth? ly= 8.6
The distance, to the nearest tenth, is 314.9 light-years.
The given data is:
A recently discovered planet is located 1.85*10^5 miles from Earth.
Now we want to transform this distance to light-years.
Remember that a light-year is defined as "the distance that the light would travel in one year".
using the relation:
distance = speed*time
The speed of light is:
speed = 6.706*10^8 mi/h
And in one year has 8760 hours, then we have:
time = 8760 h
replacing these in the equation we get:
distance = speed*time
distance = (6.706*10^8 mi/h)*(8760 h) = 5,874,456,000,000 miles
Son one light-year is equivalent to 5,874,456,000,000 miles
1 light-year = 5,874,456,000,000 miles
So to transform a distance in miles to light-years, we just need to divide that distance by 5,874,456,000,000 miles:
The distance between the new planet and Earth was:
D = 1.85*10^15 mi = ( 1.85*10^15)/(5,874,456,000,000) = 314.9 light-years.
if you want to learn more about this, you can read:
https://brainly.com/question/1302132
Do cheese and chips good?
The first periodic table of elements Mendeleev created contained only 70 elements. True or false?
Explanation:
FALSE
The first periodic table of elements Mendeleev created contained 63 elements.
What are the units for speed?
O A. km/s2
O B. m/s2
O C. m/s2
O D. m/s
Answer:
Explanation:
The only one that doesn't have a time unit that is squared is the one that is a label for speed or velocity. Acceleration has a label with the time unit squared, like m/s/s. Choice D is the only unit for speed/velocity.
Answer: D
Explanation: metres per second (m/s)
if a person buys 10 kg apples in himalayan region and sells in terai region will he get profit or loss. why?
Answer:
he will be in profit
Explanation:
Himalayan region are high above the sea level so the gravity will be less there compared to the Terai region
Terai lies way below he Himalayan region so the pull of gravity will be more compared to Himalayan region
that's why he will be in profit but not loss
a motorcycle covers 500 meters in 25 seconds. calculate the average velocity
Vtb xe máy là:
v=s : t= 500 : 25=20(m/s)
In a simple machine the energy input is 120J if the efficiency of the machine is 80% calculate the energy output
Answer:
24J
Explanation:
The energy output will be the 20% it lost in efficiency:
120-80% = 24J
The 11 th one please! Somebody help me:(
Answer:
203360Pa
Explanation:
Pressure= density of liquid*height*g
=1000*10*10
=100000Pa
Total pressure= water pressure + atmospheric pressure
=1000000+103360
=203360 Pascal
Si dejamos caer un objeto desde una gran altura, ¿será que tiene siempre la misma velocidad
Answer:
asdiieiwihebebwiwo3o2iwjw3
A cyclist competes half round of a circular track of a diameter 636m in 1.5 minutes . find the velocity
Answer:
Given information:-
Radius of the circular track is 636 mThe time elapsed in the journey is 1.5 min or 90 sThe distance traveled by the cyclist is semi circumference of the circle = πr[tex]\clubsuit[/tex]The displacement of the cyclist will be shortest distance from his initial to final positions which is nothing but diameter of the circle = 2r
We know that,
[tex] \underline{ \boxed{ \sf{Speed = \frac{Distance \: covered }{Time \: taken}}}}[/tex]
[tex]\longrightarrow \sf{\frac{636 \times 3.14 m}{90s}} \\ \\ \longrightarrow \sf22.18 m/s[/tex]
Speed of the cyclist is 22.18 m/s[tex]\sf{Velocity = \frac{Displacement }{ Time} }[/tex]
[tex]\longrightarrow \sf{ \frac{2 \times 636m}{90s} } \\ \\ \longrightarrow \sf{14.13 \: m/s}[/tex]
Velocity of the cyclist is 14.13 m/sThank You :)
please help me guys never mind the calculations
The shape is connected in parallel so;
5.1) Ans;
[tex] \frac{1}{R} = \frac{1}{R1} + \frac{1}{R2} \\ \frac{1}{R} = \frac{1}{2} + \frac{1}{3} \\ \frac{1}{R} = \frac{3 + 2}{6} = \frac{5}{6} \\ R = \frac{6}{5} = 1.2 \: \: ohm[/tex]
5.2) Ans;
[tex] \frac{1}{R} = \frac{1}{R1} + \frac{1}{R2} \\ \frac{1}{R} = \frac{1}{8} + \frac{1}{10} \\ \frac{1}{R} = \frac{5 + 4}{40} = \frac{9}{40} \\ R = \frac{40}{9} = 4.4 \: \: ohm[/tex]
I hope I helped you^_^
state the formula for period of sham in terms of acceleration and displacement
Answer:
Finding time period of SHM from equation of displacement
Explanation:
0
Say for example I've got the equation of a SHM as:
x=Acos(ωt+ϕ)
where A is the amplitude.
How do I find the time period of this motion?
I tried by finding the second order differential of the given equation.
a=d2xdt2=−Aω2cos(ωt+ϕ)
Comparing it with the general equation for acceleration a=−ω2x, we can find ω from here.
But that is where the problem is coming. It makes no sense if I write ω=ωA−−√.
What is the correct method to find the time period of the SHM? What am I missing?
There is a very simple mistake in your math. Notice A is part of x, it is factored so you'll get to ω=ω again. If you want to find a meaning to ωT=2π, consider the fact that cos (or sin) are periodic functions with period 2π. Hence, every time you have a time difference such that ω(t1−t2)=2π you are back at the same point. Hence the period is given by ωT=2π.
I want the answer for the forth question
(4)
Answer:
4 d
Explanation:
because the spring is balanced with t
If you could travel 900 meters in 55 seconds, what is your speed?
(Answer in details=brainliest)
Answer:
The rate of change of distance is called speed it can also be defined as distance travelled per unit time,from these definition you can tell that the formula will be
speed=distance/time
in this question the distance is 900meters and the time is 55seconds therefore the speed will be:
s=900meters/55seconds
=16.36m/s
I hope this helps
Which of the elements below have seven electrons in their outermost energy levels? A.) Cr, Mn, and Fe B.) Br, I, and Ci C.) O, S, and Se D.) He, Ne, and Ar
Answer:
B
Explanation:
the Halogen families have 7 valence electrons
A car travels first 10 km in 20 minutes and another 10 km in 30 minutes. What is the average speed of the car in m/s?
Total distance = 10 km + 10 km = 20 km
1 km = 1000 m
20km x 1000 = 20,000 m
Total time = 20 min. + 30 min. = 50 minutes
Average speed = Distance / time
Average speed = 20,000/50 min
Average speed = 400 m/s
Who would most likely be required to work with sodium hydroxide?
Answer:
a plumber
Explanation:
steel wire 8m long and 4mm in diameter is fixed to two rigid b. [1] supports. Calculate the increase in tension when the temperature falls by 10°C. Given linear expansivity of steel, a 12x10 %/K, Young's modulus for steel, Y = 2x10¹¹ N/m².
Answer:
301.6 N
Explanation:
The length of the wire L₀ = 8 m and its diameter, d = 4 mm = 4 × 10⁻³ m. Since its temperature drops by 10°C, it will have a change in length ΔL = L₀αΔθ where α = linear expansivity of steel, a 12 × 10⁻⁶ /K, and Δθ = temperature change = -10°C = -10 K(negative since it is a drop)
So, the strain, ε = ΔL/L₀ = αΔθ = 12 × 10⁻⁶ /K × 10 K = 12 × 10⁻⁵
Now the Young's modulus of steel, Y = σ/ε where σ = stress = T/A where T = increase in tension in steel wire and A = cross-sectional area of wire = πd²/4 where d = diameter of wire = 4 × 10⁻³ m and ε = strain = 12 × 10⁻⁵
So, σ = Yε
Since Y = 2 × 10¹¹ N/m².
Substituting the values of the variables into the equation, we have
σ = Yε
σ = 2 × 10¹¹ N/m² × 12 × 10⁻⁵
σ = 24 × 10⁶ N/m²
Since σ = T/A
T = σA
T = σπd²/4
Substituting the values of the variables into the equation, we have
T = σπd²/4
T = 24 × 10⁶ N/m² × π × (4 × 10⁻³ m)²/4
T = 24 × 10⁶ N/m² × π × 16 × 10⁻⁶ m²/4
T = 24 × 10⁶ N/m² × π × 4 × 10⁻⁶ m²
T = 96 N × π
T = 301.59 N
T ≅ 301.6 N
So, the increase in tension in the steel wire is 301.6 N
if the radius of a coin is 1 cm then calculate its area.
Answer:
3.14*1²
3.14 cm²
I hope this will help
Answer:
3.14 cm squared
Explanation:
I hope this will help.
A apartie undergoes two displacement.The one has amagnitude of 150cm and makes an angle of 120 degrees with that positive x-axis.The resultant of the two displacement is 140cm at 35 degrees to the positive x-axis .Find the magnitude and direction of second displacement
Answer:
A = 150 cm at 120 degc
Where A + B = C find B
B = C - A add -A to both sides
Ax = 150 cos 60 = -75
Ay = 150 sin 60 = 129.9
Likewise
Cx = 114.7
Cy = 80.3
Bx = Cx - Ax = 114.7 + 75 = 189.7
By = Cy - Ay = 80.3 -129.9 = -49.6
B = (189.7^2 + 49.6^2)^1/2 = 196.7 length of B vector
tan B = By / Bx = -49.6 / 189.7 B = -14.65 deg
Also
sin B = By / B = -49.6 / 196.1 = -14.65 deg
So B is 196.1 cm at -14.65 deg
