Give Reason.......Why we use life jackets when we go in the water ???
Answer:
so we don't drown and die.
Explanation:
the moon's mass is ____?
Answer:
7.35..kg
Explanation:
Hope this will help you
Please,Mark me as Brainllist .
A 50 kg girl in a roller coaster with a speed of 30 m/s is traveling around a horizontal circle with a radius of 25 m. What is the centripetal force acting on the girl.
Answer:
F=mv^2/r = 50x(900)/625 = 72N
The centripetal force of 180 N is acting on the girl who is in the roller coaster ride with a speed of 30 m/s in a horizontal circle with a radius of 25m.
What is Centripetal force?
A centripetal force is the force which makes a body follow a circular path. Here, the direction is always orthogonal to the motion of body and towards a fixed point of instantaneous center of curvature of path.
The centripetal force acting on an object in circular path can be calculated with the help of a formula:
F = mv²/r
where, F = centripetal force acting on the object,
m = mass of the object,
v = velocity of the object,
r = radius of the circular path.
By putting the given values into the formula, we get:
F = [50 × (30)²]/25
F = [50 × 900]/25
F = 4500/25
F = 180 N
Therefore, the centripetal force acting on the girl is 180 N.
Learn more about Centripetal force here:
https://brainly.com/question/14021112
#SPJ2
Initial velocity vector vA has a magnitude of 3.00 meters per second and points 20.0o north of east, while final velocity vector vB has a magnitude of 6.00 meters per second and points 40.0o south of east. Find the magnitude and the direction of the change in velocity vector Δv (which is the vector subtraction of the two vectors: final velocity vector minus initial velocity vector).
Answer:
[tex]5.2\ \text{m/s}[/tex]
[tex]70^{\circ}[/tex] south of east
Explanation:
[tex]v_a[/tex] = 3 m/s
[tex]\theta_a[/tex] = [tex]20^{\circ}[/tex] north of east
[tex]v_b[/tex] = 6 m/s
[tex]\theta_b[/tex] = [tex]40^{\circ}[/tex] south of east = [tex]360-40=320^{\circ}[/tex] north of east
x and y component of [tex]v_a[/tex]
[tex]v_{ax}=v_a\cos \theta\\\Rightarrow v_{ax}=3\times \cos 20^{\circ}\\\Rightarrow v_{ax}=2.82\ \text{m/s}[/tex]
[tex]v_{ay}=v_a\sin\theta\\\Rightarrow v_{ay}=3\times \sin20^{\circ}\\\Rightarrow v_{ay}=1.03\ \text{m/s}[/tex]
x and y component of [tex]v_b[/tex]
[tex]v_{bx}=v_b\cos \theta\\\Rightarrow v_{bx}=6\times \cos 320^{\circ}\\\Rightarrow v_{bx}=4.6\ \text{m/s}[/tex]
[tex]v_{by}=v_b\sin\theta\\\Rightarrow v_{by}=6\times \sin320^{\circ}\\\Rightarrow v_{by}=-3.86\ \text{m/s}[/tex]
[tex]\Delta v=v_b-v_a\\\Rightarrow \Delta v=(4.6-2.82)\hat{i}+(-3.86-1.03)\hat{j}\\\Rightarrow \Delta v=1.78\hat[i}-4.89\hat{j}[/tex]
Magnitude
[tex]|\Delta v|=\sqrt{(-4.89)^2+1.78^2}\\\Rightarrow \Delta v=5.2\ \text{m/s}[/tex]
Direction
[tex]\theta=\tan{-1}|\dfrac{-4.89}{1.78}|\\\Rightarrow \theta=70^{\circ}[/tex]
The magnitude of the change in velocity vector is [tex]5.2\ \text{m/s}[/tex] and the direction is [tex]70^{\circ}[/tex] south of east.
The change in velocity will be [tex]\Delta V=5.2\ \frac{m}{s}[/tex] and the direction will be [tex]70^o[/tex] South to east.
What are vector quantities?Any quantity which is defined by its magnitude and direction both are called as the vector quantities.
Now the data given in the question will be given as:
[tex]V_a[/tex] = 3 m/s
[tex]\theta[/tex] = [tex]20^o[/tex] north of east
[tex]V_b[/tex] = 6 m/s
[tex]\theta[/tex] = [tex]40^o[/tex]south of east = 360-40=320 north of east
Now we will find the x and y component of [tex]V_a[/tex]
[tex]V_{ax}=V_acos\theta[/tex]
[tex]V_{ax}=3\times Cos20[/tex]
[tex]V_{ax}=2.82\ \frac{m}{s}[/tex]
[tex]V_{ay}=V_aSin\theta[/tex]
[tex]V_{ay}=3\times Sin20[/tex]
[tex]V_{ay}=1.03\ \frac{m}{s}[/tex]
Now we will find the x and y component of [tex]V_b[/tex]
[tex]V_{bx}=V_bcos\theta[/tex]
[tex]V_{bx}=6\times cos\320[/tex]
[tex]V_{bx}=4.6\ \frac{m}{s}[/tex]
[tex]V_{by}=V_bSin\theta[/tex]
[tex]V_{by}=6\times Sin320[/tex]
[tex]V_{by}=-3.86\ \frac{m}{s}[/tex]
Now change in velocity will be
[tex]\Delta V=V_b-V_a[/tex]
[tex]\Delta V=(4.6-2.82)i+(-3.86-1.03)j[/tex]
[tex]\Delta V=1.78i-4.89j[/tex]
The magnitude can be find out as follows:
[tex]\Delta V=\sqrt{(-4.89^2+(1.78^2)}[/tex]
[tex]\Delta V=5.2\ \frac{m}{s}[/tex]
The direction of the vector will be
[tex]\theta= tan^{-1}(\dfrac{-4.89}{1.78})[/tex]
[tex]\theta=70^o[/tex]
Thus the change in velocity will be [tex]\Delta V=5.2\ \frac{m}{s}[/tex] and the direction will be [tex]70^o[/tex] South to east.
To know more about Vectors follow
https://brainly.com/question/25705666
Can you somebody answer this question for me please?
Answer:
The answer is B - the bending of rock layers happens due to stress, and this process is called folding. Faults are when it looks broken/displaced
Where does the pendulum have 100 J of potential energy?
Answer:
Potential energy is related to mass and height. More context is required otherwise the answer here is an equation with several unknowns. PE = mgL(1 – COS θ) where θ is the angle away from the vertical and L is the length of the string.
Explanation:
Pls help with all questions dew in 10 minutes!
What must be true about a surface in order for diffuse reflection to occur?
Answer:
carpet
Explanation:
Diffuse reflection is the reflection of light from a surface such that an incident ray is reflected at many angles rather than at just one angle as in the case of specular reflection.
The structure of carpet's surface is as shown. Thus it shows large amount of diffuse reflection.
How many calories are released when 6 grams of 100°C steam turns to 0°C ice?
Answer: 4276.2 calories
Explanation:
Given
mass of steam is 6 gm at [tex]100^{\circ}C[/tex]
Conversion of steam to ice involves
steam to water at [tex]100^{\circ}C[/tex]water at [tex]100^{\circ}C[/tex] to water at [tex]0^{\circ}C[/tex]water to the ice at [tex]0^{\circ}C[/tex]Calories released during the conversion of steam to water at [tex]100^{\circ}C[/tex]
[tex]E_1=mL_v\quad [L_v=\text{latent heat of vaporisation}]\\E_1=6\times 533=3198\ cal.[/tex]
Calories released during the conversion of water at [tex]100^{\circ}C[/tex] to water at [tex]0^{\circ}C[/tex]
[tex]E_2=mc(\Delta T)\quad [c=\text{specific heat of water,}1\ cal./gm.^{\circ}C]\\E_2=6\times 1\times 100=600\ cal.[/tex]
Calories released during the conversion of water to the ice at [tex]0^{\circ}C[/tex]
[tex]E_3=mL_f\quad [L_f=\text{latent heat of fusion}]\\E_3=6\times 79.7=478.2\ cal.[/tex]
The total energy released is
[tex]E=E_1+E_2+E_3\\E=3198+600+478.2=4276.2\ cal.[/tex]
How does creativity affect scientific work?
Answer & Explanation:
In science, rationality and creativity work together. Creativity allows us to view and solve problems with innovation and openness. Scientific theories often came from sparks of creative thinking and bold yet logical processes.
please help me !!!! i really need it
Answer:
Prefer Soil more than sand
Explanation:
1) Si un mango cae a una velocidad de 75m/s y tarda 26 seg. en caer. ¿ Cuál habrá sido la velocidad con qué el mango llegó al suelo?
Answer:
El mango llega al suelo a una velocidad de 329.982 metros por segundo.
Explanation:
El mango experimenta un movimiento de caída libre, es decir, un movimiento uniformemente acelerado debido a la gravedad terrestre, despreciando los efectos de la viscosidad del aire y la rotación planetaria. Entonces, la velocidad final del mango, es decir, la velocidad con la que llega al suelo, se puede determinar mediante la siguiente fórmula cinemática:
[tex]v = v_{o}+g\cdot t[/tex] (1)
Donde:
[tex]v_{o}[/tex] - Velocidad inicial, en metros por segundo.
[tex]v[/tex] - Velocidad final, en metros por segundo.
[tex]g[/tex] - Aceleración gravitacional, en metros por segundo al cuadrado.
[tex]t[/tex] - Tiempo, en segundos.
Si sabemos que [tex]v_{o} = -75\,\frac{m}{s}[/tex], [tex]g = -9.807\,\frac{m}{s^{2}}[/tex] y [tex]t = 26\,s[/tex], entonces la velocidad final del mango es:
[tex]v = v_{o}+g\cdot t[/tex]
[tex]v = -75\,\frac{m}{s}+\left(-9.807\,\frac{m}{s} \right)\cdot (26\,s)[/tex]
[tex]v = -329.982\,\frac{m}{s}[/tex]
El mango llega al suelo a una velocidad de 329.982 metros por segundo.
The base of a box is .45 m by .65 m. It weighs 8694 N. What is the pressure exerted on the floor by the box?
Answer:
[tex]Pressure = 29723.1\ N/m^2[/tex]
Explanation:
Given
[tex]Force = 8694N[/tex]
[tex]Length = 0.45m[/tex]
[tex]Width = 0.65m[/tex]
Required
The force exerted on the floor by the box
First, calculate the area covered by the box (i.e. the base area)
[tex]Base\ Area = Length * Width[/tex]
[tex]Base\ Area = 0.45m * 0.65m[/tex]
[tex]Base\ Area = 0.2925m^2[/tex]
Pressure is calculated as:
[tex]Pressure = \frac{Force}{Area}[/tex]
[tex]Pressure = \frac{8694N}{0.2925m^2}[/tex]
[tex]Pressure = 29723.0769231\ N/m^2[/tex]
[tex]Pressure = 29723.1\ N/m^2[/tex] --- approximated
A pumpkin is thrown horizontally off of a building at a speed of 2.5 — and travels a horizontal distance of
12 m before hitting the ground. We can ignore air resistance.
What is the vertical velocity when it hits the ground
Answer:
Explanation:
This is a missile throwing exercise, let's find the distance
x = v₀ₓ / t
t = v₀ₓ / x
let's calculate
t = 2.5 / 12
t = 0.2083 s
as time is a scalar this is the same value for descends to the ground
y = v_{oy} t - 1/2 g t²
we calculate
v_y = 0 - 9.8 0,2083
v_y = - 2.04 m / s
the negative sign indicates that the speed is down
A pumpkin is thrown horizontally off of a building at a speed of 2.5 m/s and travels a horizontal distance of 12 m before hitting the ground. We can ignore air resistance.
What is the pumpkin's vertical velocity when it hits the ground?
Answer: -47.04
HELP ME
PLZZZ
ASAP
HELP
LIFE
OR
DEATH
SITUATION
The half-life of carbon-14 is 5730 years.
Carbon-14 is used for carbon dating. Carbon dating can tell us how old some
objects are
A skeleton was carbon dated. The results showed that there was only 12.5% of the
original amount of carbon-14 left in the skeleton.
Calculate the age of the skeleton.
HELP ASAP PLZZZ I BEG YOUUUU
Answer:
13,308 MAYBE IF IT ISN'T IM SO SORRY
Explanation:
Is O2 classified as a compound?
Answer: NO.
Explanation: Oxygen is not a compound. It has only one element in it.
El monoxido de carbono reacciona con el hidrogeno gaseoso para producir metanol (ch3oh) calcule el reactivo limite y el reactivo en exceso si la reaccion inicia con 2,0 g de cada reactivo calcule cuantos gramos de metanol se obtiene
Answer:
Se obtienen 2,27 gramos de metanol.
Explanation:
La reacción entre monóxido de carbono e hidrógeno para producir metanol es la siguiente:
CO + 2H₂ → CH₃OH
Para encontrar el reactivo limitante y el reactivo en exceso, debemos calcular el número de moles de CO y H₂:
[tex]\eta_{CO} = \frac{m}{M} [/tex]
En donde:
m: es la masa
M: es el peso molecular
[tex]\eta_{CO} = \frac{m}{M_{CO}} = \frac{2,0 g}{28,01 g/mol} = 0,071 moles [/tex]
[tex]\eta_{H_{2}} = \frac{2,0 g}{2,02 g/mol} = 0,99 moles [/tex]
Dado que la relación estequiométrica entre CO y H₂ es 1:2, el número de moles de hidrógeno gaseoso que reaccionan con el monóxido de carbono es:
[tex] \eta_{H_{2}} = \frac{2}{1}*0,071 = 0,142 moles [/tex]
Entonces, se necesitan 0,142 moles de H₂ para reaccionar con 0,071 moles de CO y debido a que se tienen más moles de H₂ (0,99 moles) entonces el reactivo limitante es CO y el reactivo en exceso es H₂.
Ahora podemos encontar la masa de metanol obtenida usando el reactivo limitante (CO) y sabiendo que la realcion estequiométrica entre CO y CH₃OH es 1:1.
[tex] \eta_{CH_{3}OH} = \eta_{CO} = 0,071 moles [/tex]
[tex] m = 0,071 moles*32,04 g/mol = 2,27 g [/tex]
Por lo tanto, se obtienen 2,27 gramos de metanol.
Espero que te sea de utilidad!
PLEASE HELP ME I AM TIMED!
Answer: B
Explanation: I can tell the block weights more since the water went down
Which of the following is another name for a convex lans?
O Diverging liens
3. Converging lens
O c Shrinking lans
OD Security lans
Answer:
3. converging lens
Explanation:
When the rays of light coming parallel to principle axis after refraction through the lens passes through a point called focus, since it converge all the ray at one point, that is why it is said to be converging lens.
Please help me if you can.
I can't figure out how the answer for number 30 is C and 31 is C. My question is how did they get that answer?
Answer:
30. $3.85
31. $2.22
Explanation:
30. The time duration of the kitchen clock is left on = All day = 24 hours
The power rating of the kitchen clock, P = 4 watts
The electricity cost in Alberta, R = $0.11 per kilowatt hour
The total number of hours the kitchen clock is on during the year, 't', is given as follows;
t = Number of hours per day × Number of days per year
∴ t = 24 hours/day × 365 days/year = 8,760 hours
The energy consumption of the kitchen clock, per year, E = P × t
∴ E = 4 watts × 8,760 hours = 35,040 watts-hour = 35.040 kw·h
The cost of operating the clock in one year, C = E × R
∴ Operating cost for the kitchen clock
∴ C = 35.040 kw·h × $0.11/(kw·h) = $3.8544 ≈ $3.85
The cost of operating the clock in one year, C ≈ $3.85
31. The power rating of the ghetto blaster, P = 28 watts
The time duration the ghetto blaster was on during an average month = All day = 24 hours
The number of days during an average month, n = 30 days
The cost of electricity in Alberta, R = $0.11 per kilowatt hour
The time in hours the ghetto blaster was on, t = 30 days/month × 24 hours/day
∴ t = 720 hours per month
The cost of operating the ghetto blaster in one month, C = P × t × R
∴ C = 28 W × 720 hours × 1 kw·h/(1000 w·h)× $0.11/(kw·h) = $2.2176
∴ The cost of operating the ghetto blaster in one month, C ≈ $2.22
how long would it take a leopard, running at an average speed of 20 m/s to travel 500 m?
Answer:
25 seconds
Explanation:
500/20
How many people does it take to change a lightbulb?
phase difference formula
Answer:
Δx is the path difference between the two waves.
...
Phase Difference And Path Difference Equation.
Formula Unit
Phase Difference \Delta \phi=\frac{2\pi\Delta x}{\lambda } Radian or degree
Path Difference \Delta x=\frac{\lambda }{2\pi }\Delta \phi meter
A material kept at high temperature is seen to emit photons with energies of 0.3 eV, 0.5eV, 0.8 eV, 2.0 eV, 2.5 eV, and 2.8 eV. These are the only photon energies observed. It is now cooled down to a very low temperature so that it is not emitting photons anymore. If a beam of light with a continuous range of energies from 0.01 eV to 10 eV shines on the material, what photon energies in this beam will correspond to dark absorption lines?
1. 0.3 eV, 0.5 eV, 2.8 eV
2. 0.3 eV, 0.5 eV, 0.8 eV
3. 0.3 eV, 0.8 eV, 2.8 eV
4. 0.8 eV, 2.0 eV, 2.8 eV
5. 0.5 eV, 0.8 eV, 2.8 eV
6. 0.3 eV, 2.5 eV, 2.8 eV
Answer:
the correct one is 2
Explanation:
The emission and arcion spectra are similar, in the emission spectra a heated material emits photons for the internal transitions of the electrons, in the absorption spectrum the continuous emission of a lamp is absorbed at the energies that the material has transitions.
In our case the material is low early, so all the electrons are in their base states.
As the light beam has all wavelengths, those corresponding to the first emission of the material will be observed.
When reviewing the answers, the correct one is 2
2. Why do you fall forward when you stub your toe on a chair? Explain in terms (meaning use
the words in the law in your answer) of inertia and Newton's llaw.
STUBBED
MY TOES
3. Why do you fly forward when hitting a curb while riding a skateboard or bike? Explain in
terms of inertia and Newton's 1" law.
4. Come up with your own example of Newton's first lawl Again explain using inertia and
Newton's l1st law
Answer:
because u feel pain and u get shaky and fall
Explanation:
Answer:
Explanation:because it hurts so you fall
An athletes heart beats 62 times per minute. What is the frequency of her heart beat?
Answer:
22
Explanation:
bc it just is
LOTS OF BRAINLIST WILL BE GIVING TO THOSE WHO HELP
chemical reaction for fossil fuels:combustion of fuels.
Difference between biomass and fossil fuels:how much carbon dioxide is produced
Comparing biomass with other renewable energy sources:does not have as much energy potential as fossil fuels.
Making energy choices locally: biomass
Explain how it is that you could have 2 parents with brown eyes, but you have blue eyes. Talk about the role chromosomes, genotypes, and alleles play in making something like that happen.
Help please will give b to the best one!
Answer:
Because the two genes depend on each other, it is possible for someone to actually be a carrier of a dominant trait like brown eyes. And if two blue eyed parents are carriers, then they can have a brown eyed child. Genetics is much bkj
Explanation:
So all you light eyed parents with dark eyed kids, stop asking those paternity questions (unless you have other reasons to be suspicious). Darker eyed kids are a real possibility that can now be explained with real genes.
A contour map has 14 concentric circles, each placed 1/2 centimeters apart. The map's scale indicates 1cm = 10 ft. What is the structure, and what are its dimensions?
Answer:
B. A hill 70ft tall.
Explanation:
A transverse wave vibrates its medium __________ to the forward motion of the wave, and a longitudinal wave vibrates its medium __________ to the forward motion of the wave.
perpendicular; circularly
parallel; circularly
parallel; perpendicular
perpendicular; parallel
Answer:
Perpendicular ; Parallel