Up until the moment the box starts to slip, the static friction is maximized with magnitude f, so that by Newton's second law,
• the net force acting on the box parallel to the ramp is
∑ F = mg sin(α) - f = 0
where mg sin(α) is the magnitude of the parallel component of the box's weight; and
• the net force acting perpendicular to the ramp is
∑ F = n - mg cos(α) = 0
where n is the magnitude of the normal force and mg cos(α) is the magnitude of the perpendicular component of weight.
From the second equation we have
n = mg cos(α)
and f = µn = µmg cos(α), where µ is the coefficient of static friction. Substituting these into the first equation gives us
mg sin(α) = µmg cos(α) ==> µ = tan(α) ==> α = arctan(0.35) ≈ 19.3°
Which of the following elements has the largest atomic radius?
Silicon
Aluminum
Sulfur
Phosphorous
Answer:
francium
Atomic radii vary in a predictable way across the periodic table. As can be seen in the figures below, the atomic radius increases from top to bottom in a group, and decreases from left to right across a period. Thus, helium is the smallest element, and francium is the largest.
A swimmer heading directly across a river that is 200 m wide reaches the opposite bank in 6 min 40 s. During this swim, she is swept downstream 480 m. How fast can she swim in still water
Answer:
The speed of the swimmer in stil water is 0.5 m/s
Explanation:
Given;
total time taken to swim across = 6 mins 40 s = (6 x 60s) + 40 s = 400 s
width of the river, = 200 m
Please find the image attached for explanation.
A pilot wishes to fly from Bayfield to Kitchener, a distance of 100 km on a bearing of 105°. The speed of the plane in still air is 240 km/h. A 20 km/h wind is blowing on a bearing of 210°.
Remembering that she must fly on a bearing of 105° relative to the ground (i.e. the resultant must be on that bearing), find (6 marks)
a) the heading she should take to reach her destination.
b) how long the trip will take.
An empty 12,954 kg railroad car, traveling at a speed of 28 m/s strikes a partially filled 17,616 kg railroad car moving in the same direction at a speed of 5 m/s. What is the total momentum of the two railroad cars AFTER the collision?
Answer:
450792 kgm/s
Explanation:
by conservation of momentum,
total momentum AFTER collision = total momentum BEFORE collision
=mv+m'v'
=12954×28+17616×5
=450792 kgm/s
A train moves with a uniform velocity of 36km/hr 10sec. calculate the distance travelled
Given:-
Speed = 36 km/hr
converting speed into m/s
Speed = 36*5/18
Speed = 10 m/s
t = 10 sec
By using the Formula
Distance = Speed * time
D = 10*10
D = 100 m
Hope it helps....
According to Coulomb's law, if the separation between two particles of the same charge increases four times, the potential energy of the two particles:__________.
a. is one-sixteenth as high as it was before the separation.
b. is four times as high as it was before the distance separation.
c. is one-fourth as high as it was before the separation.
d. does not change.
Answer:
c. V = k Q1 * Q2 / R1 potential energy of Q1 and Q2 separated by R
V2 / V1 = (R1 / R2) = 1/4
V2 = V1 / 4
According to Coulomb's law, if the separation between two particles of the same charge increases four times, the potential energy of the two particles is is one-fourth as high as it was before the separation. The correct option is c.
What is Coulomb's law?Coulomb's law states that the force of attraction or repulsion among both two charged bodies is directly related to the sum of their charges and inversely proportional to the square of the distance between them.
Coulomb force is the attraction or repulsion of particles or objects due to their electric charge. It is also known as electrostatic force or Coulomb interaction.
It denotes the electric force's inverse square dependence. It can also be used to accurately provide relatively simple derivations of Gauss' law for general cases.
Coulomb's law states that if the separation between two particles of the same charge increases four times, the potential energy of the two particles is one-fourth of what it was before the separation.
Thus, the correct option is c.
For more details regarding Coulomb's law, visit:
https://brainly.com/question/506926
#SPJ2
Problem
A charged particle is moving in the presence of uniform magnetic field. The mass of the particle
is m = 10−6 kg its charge is Q = 10−5 C and the magnetic field vector is B~ = (1T, 0, 0). At the
beginning the velocity vector of the particle is ~v0 = (12 m/s, 0, 5 m/s).
a.) How large will the x component of the velocity of the particle be in t = 2 s?
b.) Where will the particle be in t = 3.14 s?
c.) How large will the magnitude of the velocity be in t = 2.5 s?
Answer:
Answer is a I checked the work
BRAINLY PLS HELP ME!!!
Should the Us government regulate sugar? In once sentence write down what you are preparing to argue or what stance you are going to take. This will help you to create a starting point for your idea
Answer:
yes
Explanation:
Sugar can cause health problems.
I believe that sugar should be regulated by the government since it causes heath problems. As according to this website heathline.com that up to one third of the population in America is obese. As well as that regulating sugar will greatly help lowering that number, seeing that many food products have tons of sugar in them. By lowering the sugar and regulating it can cause less obesity among the average person in the US. As stated by HeathlyFoodAmerca.org consuming too much sugar can cause increased heath problems as shown, heart disease, diabetes, and teeth decay and this is why I believe that the U.S government should regulate sugar more.
A ball is thrown horizontally at a speed of 24 meters per second from the top of a cliff. If the ball hits the ground 6.0 seconds later, approximately how high is the cliff?
Answer:
144 meters
Explanation:
it takes 6 seconds to hit the ground right and the ball lays off 24 m per second .
so by the time the ball hits the ground 6 seconds passed. so that means the cliff is 6.0×24=144
Two thin conducting plates, each 56.0 cm on a side, are situated parallel to one another and 7.0 mm apart. If 10^-10 electrons are moved from one plate to the other, what is the electric field between the plates?
Answer:
[tex]E=576.5V/m[/tex]
Explanation:
From the question we are told that:
Length [tex]l=56.0cm=0.56m[/tex]
Distance apart [tex]d=7.0mm=0.007m[/tex]
Electron Transferred [tex]n=10^{-10}[/tex]
Therefore
Total Charge
Since Charge on each electron is
[tex]e=1.602*10^{-19}[/tex]
Therefore
[tex]T=1.602*10^{-19} *10^{10}[/tex]
[tex]T=1.602*10^{-9}[/tex]
Generally the equation for Charge density is mathematically given by
[tex]\rho=T/A[/tex]
Where
Area
[tex]A=0.56*0.56[/tex]
[tex]A=0.3136[/tex]
Therefore
[tex]\rho=1.602*10^{-9}/0.3136[/tex]
[tex]\rho=5.10*10^{-9}[/tex]
Generally the equation for Electric Field in the capacitor is mathematically given by
[tex]E=\frac{\rho}{e_0}[/tex]
[tex]E=\frac{5.10*10^{-9}}{8.85x10{-12}}[/tex]
[tex]E=576.5V/m[/tex]
assuming a filament in a 120W light bulb acts like a prefect blackbody, what is the temperature of the hottest portion of the filament if it has a surface area of 6.4×10^_5m^2. The stefan- boltzmann constant is 5.67×10^-8W/(m2.k2) A. 12OOk B. 2400K C. 2100K
Answer:
T = 2398 K
Explanation:
To calculate the emission of the light bulb we use the law is Stefan
P = σ A e T⁴
as they indicate that the filament is a black body, the emissivity is equal to 1 (e = 1)
T = [tex]\sqrt[4]{\frac{P}{ \sigma A} }[/tex]
let's calculate
T =[tex]\sqrt[4]{\frac{120}{5.67 \ 10^{-8} \ 6.4 \ 10^{-5}} }[/tex]
T = [tex]\sqrt[4]{33.06878 \ 10^{12} }[/tex]
T = 2,398 10³ K
T = 2398 K
differentiate between step up and step down transformer
Answer:
The main difference between the step-up and step-down transformer is that the step-up transformer increases the output voltage, while the step-down transformer reduces the output voltage.
1. Convert the following length into meters
a. 123.50mm
b. 560cm
c. 100dm
d. 125.89km
You swing a bat and hit a heavy box with a force of 1273 N. The force the box exerts on the bat is Group of answer choices less than 1273 N if the box moves. exactly 1273 N whether or not the box moves. None of the above choices are correct. exactly 1273 N only if the box does not move. greater than 1273 N if the bat bounces back. greater than 1273 N if the box moves.
Answer:
exactly 1273 N whether or not the box moves.
Explanation:
In the case when the bat is swing and it is hitted to a heavy box having a force of 1273 N so here the force of the box that exert on the box should be accurately 1273 N even if the box is moved or not. As the third law of the newton should be equivalent & the opposite reaction
Therefore as per the given situation, the above represent the answer
A hoop rolls with constant velocity and without sliding along level ground. Its rotational kinetic energy is:______a- half its translational kinetic energyb- the same as its translational kinetic energyc- twice its translational kinetic energyd- four times its translational kinetic energy
Answer:
The same as its translational KE.
The easy way to do this is to make up numbers and use them.
So, I'll say m=2 and r=3. I will also say v=3 .
Rot. Inertia of a hoop is mr^2. So the rot KE is: 1/2 (mr^2)(w^2)
note: (1/2*I*w^2)
Translational kinetic energy is basically normal KE, so 1/2(m)(v^2)
Now, lets plug our made up values in:
Rot Ke : 1/2 (9*2)(3/3) *note w = v/r
Tran Ke: 1/2(2)(9)
Rot Ke: 9
Tran Ke: 9
9=9, same.
The cycle is a process that returns to its beginning, but it does not repeat
itself.
True
False
A truck is hauling a 300-kg log out of a ditch using a winch attached to the back of the truck. Knowing the winch applies a constant force of 2850 N and the coefficient of kinetic friction between the ground and the log is 0.45, determine the time for the log to reach a speed of 0.5 m/s
Answer:
0.1 s
Explanation:
The net force on the log is F - f = ma where F = force due to winch = 2850 N, f = kinetic frictional force = μmg where μ = coefficient of kinetic friction between log and ground = 0.45, m = mass of log = 300 kg and g = acceleration due to gravity = 9.8 m/s² and a = acceleration of log
So F - f = ma
F - μmg = ma
F/m - μg = a
So, substituting the values of the variables into the equation, we have
a = F/m - μg
a = 2850 N/300 kg - 0.45 × 9.8 m/s²
a = 9.5 m/s² - 4.41 m/s²
a = 5.09 m/s²
Since acceleration, a = (v - u)/t where u = initial velocity of log = 0 m/s (since it was a rest before being pulled out of the ditch), v = final velocity of log = 0.5 m/s and t = time taken for the log to reach a speed of 0.5 m/s.
So, making t subject of the formula, we have
t = (v - u)/a
substituting the values of the variables into the equation, we have
t = (v - u)/a
t = (0.5 m/s - 0 m/s)/5.09 m/s²
t = 0.5 m/s ÷ 5.09 m/s²
t = 0.098 s
t ≅ 0.1 s
A 8.37*10^-5 F capacitor has 2.15*10^-4 C of charge on its plates. How much energy is stored on the capacitor
Answer:
2.76*10^-4
Explanation:
Trust me :)
PLEASE ANSWR 1ST AND I WILL MARK U BRAINLIEST
Two statements are given- one labeled Assertion (A) and the other labeled Reason ®. Select
the correct answer to these questions from the codes (a), (b), (c) and (d) as given below:
a. Both A and R are true, and R is correct explanation of the assertion.
b. Both A and R are true, but R is not the correct explanation of the assertion.
c. A is true, but R is false.
d. A is false, but R is true.
Assertion: An object has a negative acceleration.
Reason: The velocity of an object decreases in the same direction.
Answer:
Where is the R statement?
you are given a set of facts regarding a lens : object heigh, and dostance to objects. Given this jnformation, how can you tell if you're dealing with a concave or convex lens
Answer:
concave curves inward like an hourglass and convex is an outward curve like a football
Explanation:
hope this helps
A spring scale hung from the ceiling stretches by 6.1cm when a 2.0kg mass is hung from it. The 2.0kg mass is removed and replaced with a 2.8kg mass.What is the stretch of the spring?
if p=2i+4j+3k and q=I+5j-2k,find P×q.
Answer:
[tex]p\times q=-23i+7j+6k[/tex]
Explanation:
We are given that
p=2i+4j+3k
q=i+5j-2k
We have to find pxq
We know that
[tex]p\times q=\begin{vmatrix} i&j &k\\ 2&4 & 3\\ 1& 5 & -2\end{vmatrix}[/tex]
[tex]p\times q=i(-8-15)-j(-4-3)+k(10-4)[/tex]
[tex]p\times q=-23i+7j+6k[/tex]
Hence,[tex]p\times q=-23i+7j+6k[/tex]
Given that o.2i+bj+o.4k is a unit vector,what is the value of b?
Answer:
b = 0.89
Explanation:
The given vector is, [tex]A=0.2i+bj+0.4k[/tex]
A is a unit vector
We need to find the value of b.
For a unit vector, |A| = 1
So,
[tex]0.2^2+b^2+0.4^2=1\\\\0.04+b^2+0.16=1\\\\0.2+b^2=1\\\\b^2=1-0.2\\\\b=0.89[/tex]
So, th value of b is 0.89.
During the fission reaction shown, how did the target nucleus change ?
Answer:
A. The target nucleus split into two nuclei, each with fewer nucleons than the original.
Explanation:
Answer: A. The target nucleus split into two nuclei, each with fewer nucleons than the original.
Explanation:
What is the friction force on a box that has a mass of 15kg as it slides across the floor. The coefficient of friction of the not very clean floor is 0.25
please explain everything including formula used
Answer:
36.75 N
Explanation:
Applying
F = mgμ................. Equation 1
Where F = Friction force on the box, m = mass of the box, g = acceleration due to gravity of the box, μ = coefficient of static friction
From the question,
Given: m = 15 kg, μ = 0.25
Constant: g = 9.8 m/s²
Substitute these values into equation 1
F = 15(9.8)(0.25)
F = 36.75 N
Hence the friction force on the box is 36.75 N
An electric field is given by in units of N/C when is in meters. What is the potential difference from point B at (0,7) m to point A at (7,0) m
Complete Question
An electric field is given by E= (5x, 0, 0) in units of N/C when x is in meters. What is the potential difference VA - VB from point B at (0,7) m to point A at (7,0) m? V
Answer:
[tex]V_A-V_B=-122.5V[/tex]
Explanation:
From the question we are told that:
Position of point [tex]B=(0,7) m[/tex]
Position of point [tex]A=(7,0) m[/tex]
Generally the equation for pd across the points is mathematically given by
[tex]V_A-V_B=-\int_0^7(5x)d[/tex]
[tex]V_A-V_B=-[\frac{5x^2}{2}]_0^7[/tex]
[tex]V_A-V_B=-[\frac{5(7)^2}{2}][/tex]
[tex]V_A-V_B=-122.5V[/tex]
Help!!
A table is pushed across the floor for a distance of 32 m with a force of 320 N in 150 seconds. How much power was used?
A.70.2W
B.68.3W
C.56.7W
D.49.8W
Compute the work done on the table:
W = Fd = (320 N) (32 m) = 10,240 J
Divide this by the given time duration to get the power output:
P = W/∆t = (10,240 J) / (150 s) ≈ 63.3 W
Find the ratio of the diameter of copper to iron wire, if they have the same resistance per unit length (as they might in household wiring). dCu dFe =
Answer:
The ratio of diameter of copper wire to the iron wire is 0.42.
Explanation:
length of both the wires is same as L and resistance is R.
resistivity of copper = 1.7 x 10^-8 ohm m
resistivity of iron = 9.7 x 10^-8 ohm m
Let the diameter of copper is d and for iron is d'.
The formula of the resistance is
[tex]R = \rho\times\frac{L}{A}\\\\R = \rho\times\frac{4L}{\pi d^2}.... (1)\\And\\ R = \rho'\times\frac{4L}{\pi d'^2}.... (2)\\\\comparing (1) by (2)\\\\1.7\times10^{-8}\times\frac{4L}{\pi d^2}=9.7\times10^{-8}\times\frac{4L}{\pi d'^2}\\\\d : d' = 0.42[/tex]
explain why this is important for life on earth
Answer:
THIS is very important.
Explanation:
If the word "this" was never invented, people wouldn't have a way to tell another person what is directly in front of them.
BTW this is a joke.
A constant force moves an object along the line segment from to . Find the work done if the distance is measured in meters and the force in newtons.
This question is incomplete, the complete question is;
Flag
A constant force F = 6i+8j-6k moves an object along a straight line from point (6, 0, -10) to point (-6, 7, 2).
Find the work done if the distance is measured in meters and the magnitude of the force is measured in newtons.
Answer:
the work done is -88 J
Explanation:
Given the data in the question;
we know that;
Work done = F × S
where constant force F = ( 6i + 8j - 6k )
S = ( -6i + 7j + 2k ) - ( 6i + 0j - 10k )
S = ( (-6i - 6i) + (7j - 0j) + ( 2k - ( -10k) ) )
S = ( -12I + 7j + 12k )
so
Work force = ( 6i + 8j - 6k ) × ( -12I + 7j + 12k )
Work force = ( 6 × -12 ) + ( 8 × 7 ) + ( -6 × 12 )
Work force = -72 + 56 - 72
Work force = -88 J
Therefore, the work done is -88 J
