Answer:
μ = 0.849
Explanation:
In order to solve this problem we must remember that the friction force is defined as the product of the coefficient of friction by the normal force. And normal force is defined as the component of force in the opposite direction to the weight of the body (chair).
As in the y axis there is no movement we can say that the sum of the forces on the chair is equal to zero.
∑Fy = 0
[tex]N-W=0[/tex]
where:
N = normal force [N] (units of Newtons)
W = weight of the chair = m*g [N]
m = mass = 15 [kg]
g = gravity acceleration = 9.81 [m/s²]
[tex]N=m*g\\N=15*9.81\\N=147.15 [N][/tex]
Now the key to solving this problem is to understand that we start applying force on the horizontal component until the chair starts to move at this moment the friction component is calculated with the static friction coefficient. As the chair doesn't move we can say that the sum of force in the horizontal direction is equal to zero.
∑Fx = 0
[tex]F -f_{force} = 0[/tex]
F = force applied = 125 [N]
fforce = friction force = μ*N
μ = friction coefficient (static)
N = normal force = 147.15 [N]
[tex]125-u*147.15=0\\u = 125/147.15\\u = 0.849[/tex]
A girl rides her bike at 15 m/s for 20 s. How far does she travel in that time?
We are given:
Initial Velocity(u) = 15 m/s
Time interval(t) = 20s
Solving for the distance covered:
Since the girl keeps riding her bike at 15 m/s, her speed is constant and hence, acceleration of the bike is 0 m/s²
acceleration(a) = 0 m/s²
We know that:
s = ut + 1/2(at²) [second equation of motion]
s = (15)(20) + 1/2(0)(400) [plugging the values]
s = 150 + 0
s = 300 m
Hence, the girl covered 300 m in 20 seconds
Explain how a fish is able to enjoy 180° field of view when in a pond.
Answer:
Time
An explanation of basic pond measurements that are vital to basic pond management practices.
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Pond Measurements: Area, Volume and Residence Time - Articles UPDATED: OCTOBER 29, 2015
Pond Measurements: Area, Volume and Residence Time
The importance of getting an accurate estimation of your pond surface area cannot be overestimated. The majority of pond owners visually estimate their pond area, which usually results in an overestimate of the true pond surface area. Pond area and water volume should be calculated based on some simple measurements. The effort necessary to estimate pond surface area is directly related to your pond's shape and uniformity. The simplest method--using basic equations for common shapes--can be applied if your pond closely resembles a circle, square, rectangle, or trapezoid in shape.
Pond Shapes
Circular
pond shape can be estimated by measuring the distance around the pond shoreline in feet. Square the shoreline distance and divide by 547,390 to get the pond area in acres. For example, a pond that is 450 feet around the shoreline would have an area = (450 feet)2 / 547,390 or 0.37 acres.
Explanation:
i looked this up
Which term best describes the motion of the rope particles in relation to the motion of the rope wave shown in the photograph
Answer:
A: Perpendicular
Explanation:
The question is incomplete as it lacks the image of the rope wave motion.
However, as found on "estudyassistant", the options are;
A) Perpendicular
B) Circular
C) Longitudinal
D) Parallel
From all that, we can say that;
The rope's are moving simultaneously in the same pattern without touching each other.
This is therefore a mechanical wave being created with the motion having oscillations that are perpendicular to the direction of energy transfer of the ropes.
This is a definition of transverse waves because the rope particle motion is perpendicular to the wave motion.
Answer:
A: Perpendicular
Explanation:
Read above explanation.
How long( in hours, will it take for 500 000 C of charge to flow through a diode if it requires
0.05 Amp to operate it.
Answer:
277.78 hours
Explanation:
The formula for calculating the amount of charge is expressed as;
Q = It
I is the current
t is the time
Given
I =0.05A
Q = 50,000C
Required
Time t
Recall that: Q = It
t = Q/I
t = 50,000/0.05
t = 1,000,000secs
Convert to hours
1,000,000secs = 1,000,000/3600
1,000,000secs = 277.78 hours
Hence it will take 277.78 hours for the charge to flow through the diode
A car moving initially at 20 m/s accelerates up to 60 m/s during the
course of 5 seconds. The average acceleration of the car is m/s2
What kind of energy is produce when sun reaches solar panel?
Answer:
Radient to ElEcTrIcAAl
Explanation:
The FitnessGram Pacer Test is a multistage aerobic capacity test that progressively gets more difficult as it continues. The 20 meter pacer test will begin in 30 seconds. Line up at the start. The running speed starts slowly, but gets faster each minute after you hear this signal. A single lap should be completed each time you hear this sound. Remember to run in a straight line, and run as long as possible.
Can you help with this question please thanks
Answer:
no .the blue runner began 16 m ahead of the red runner
which is NOT true of the Big Bang Theory?
1. it explains what’s happening in the universe now
2. it explains what caused the big bang.
3. it explains what the universe was like in the beginning
4. it stages that the universe is expanding
Answer:
1. it explains what's happening im the universe now
Wavelength is a measurement of ___________ , while period is a measurement of ___________ . *
Speed; time
Time; speed
Distance; time
Time; distance
Distance; speed
Speed; distance
distance ; time
Explanation:
wavelength is in metres [m]
period is in seconds [s]
calculate the force necessary to keep a mass of 2 kg moving on a circular path of radius 0.2 m with a period of 0.5 second. what is the direction of this force
what are the very small particles that make up matter
Answer:
The very small particles that make up matter are I) Atoms
Matter - Anything that have mass and occupies space is called matter . it is made up of atoms and molecules
Atoms - The smallest part of matter is called atom.
Molecule - Group of atoms combine together to form a molecule.
More to know - Atom is made up of even smaller particles called neutron, proton and electron. Electron moves around nucleus ( nucleus is made up of neutron and proton) Different types of atom combine and form molecule ( Nitrogen dioxide No2 has 1 atom of nitrogen and 2 atoms of oxygen)(a) Calculate the linear acceleration of a car, the 0.220-m radius tires of which have an angular acceleration of 11.0 rad/s2. Assume no slippage.
Answer:
The value is [tex]a_t = 2.42 \ m/s^2[/tex]
Explanation:
From the question we are told that
The radius of the tires is [tex]r = 0.22 \ m[/tex]
The angular acceleration is [tex]\alpha = 11.0 \ rad/s^2[/tex]
Generally the linear acceleration is mathematically represented as
[tex]a_t = r * \alpha[/tex]
=> [tex]a_t = 0.22 * 11[/tex]
=> [tex]a_t = 2.42 \ m/s^2[/tex]
What is the change in potential energy in moving a 10kg box from the floor to a table 1 m high?
Explanation:
potential energy formula is 1/2 mv2(this 2 is square).m means mass and v means velocity.
now, you can calculate
The change in potential energy in moving a 10kg box from the floor to a table 1 m high is 98 Joules.
To find the potential energy, the given values are,
Mass of the box = 10Kg
Height h = 1 m
What is Potential energy?The potential energy can be defined as the energy that is stored and that can be determined through various parts in a particular system.
Also, the energy will gets stored when the object is not moving.
For example: Spring. Even when the spring is not stretched or contracted it stores energy.
The formula for Potential energy PE= mgh joules.
m is the Mass,
g is the acceleration due to gravity = 9.8 m/s²,
h is the height.
Substituting all the given values,
Potential Energy= 10 (9.8)(1)
PE= 98 J
Thus the potential energy of the box= 98 J.
To learn more about the potential energy,
https://brainly.com/question/13548111
#SPJ2
What is the lithosphere?
A. the outer layer of the Earth's crust
B. the inner core
C. the middle portion of the mantle
D. the outer core
Answer:
a. outer layer
Explanation:
lithosphere is right underneath the continental and ocean crust. it is approximately 100 km in deep and it is a brittle layer. It is broken into tectonic plates.
the inner core is located at the very center and its full of iron and nickel (so its not B)
on top of that is the outer core which is liquid (not D)
the middle portion of the mantle is the asthenosphere and mesosphere. they are right beneath the lithosphere. (not C)
so the best answer is A
2. Two identical spheres having charges Q and -
2Q experience a force F at a certain distance
If the spheres are kept in contact and then
placed at same initial distance, the force
between them will be
force between the two charges (+q1 and +q2),if they are at a distance 'a' is
F1=1/4pieEo q1q2/d^2................ (1)
when the metal spheres are in contact the charge flow from one sphere to another till both the sides acquires the same charge. here q1 and q2 are of same sign,hence after contact each sphere will have a charge
[tex] \binom{q1 + q2 }{2} [/tex]
now,the force between them,
f2=1/4pieEo
(q1+q2/2)^2/d^2
from eq (1)and eq (2)
f2=f1 (q1+q2)^2/4q1q2
Briefly describe the Rutherford atomic model
Answer:
The Rutherford model was made by Ernest Rutherford, to describe a atom. That is a brief explanation
Explanation:
А
Each sentence describes potential and kinetic energy
at various locations on a slide. Complete each
statement by selecting the position of the object on the
slide.
An object at position has all kinetic energy
An object at position has all potential energy
An object at position has about half potential energy
and half kinetic energy.
B
с
Answer:
C. A. B.
Explanation:
Credit to Lainey in the comments for the answer!
Answer:
1] C
2] A
3] B
Explanation:
i just got hit on the head by a basketball.
story of my life.
Season Leaders
Go to Stats
Points Per Game
1.
Talen Horton-Tucker
26.0
2.
Nikola Jokic
26.0
3.
Zion Williamson
26.0
4.
Giannis Antetokounmpo
24.5
5.
Patty Mills
24.0
Rebounds Per Game
1.
Rudy Gobert
14.0
2.
Harry Giles III
13.5
3.
Clint Capela
13.0
4.
Nikola Vucevic
13.0
5.
Giannis Antetokounmpo
12.0
Assists Per Game
1.
Ja Morant
9.0
2.
Bam Adebayo
8.0
3.
T.J. McConnell
7.5
4.
DeMar DeRozan
7.0
5.
Spencer Dinwiddie
7.0
More Leaders
Hustle Leaders
Advanced Leaders
All Time Leaders
Since astronauts in orbit are apparently weightless, a clever method of measuring their masses is needed to monitor their mass gains or losses to adjust diets. One way to do this is to exert a known force on an astronaut and measure the acceleration produced. Suppose a net external force of magnitude 59.0 N is exerted and the magnitude of the astronaut's acceleration is measured to be 0.852 m/s2. Calculate her mass.
Answer:
The value is [tex]m = 69.24 \ kg[/tex]
Explanation:
From the question we are told that
The value of the external force is [tex]F = 59.0 \ N[/tex]
The magnitude of the astronaut's acceleration is [tex]a = 0.852 \ m/s[/tex]
Generally Newton's Second Law of Motion from the mass of the astronauts is mathematically represented as
[tex]m = \frac{F}{a}[/tex]
=> [tex]m = \frac{59 }{0.852 }[/tex]
=> [tex]m = 69.24 \ kg[/tex]
Help please I would appreciate it
Answer:
i think the red runner travels greater distance ie.40 m
Explanation:
although ,the blue one travels 21 m but in the backward direction .so the correct ans is "the red runner travels 40 m"
A 2.0 kg bucket is attached to a horizontal ideal spring and rests on frictionless ice. You have a 1.0 kg mass
that you must drop into the bucket. Where should the bucket be when you drop the mass (so it is moving
purely vertically when it lands in the bucket) if your goal is to:
(a) Maximize the amplitude of the oscillation of the resulting 3.0 kg mass and spring system.
(b) Minimize the amplitude of the oscillation of the resulting 3.0 kg mass and spring system.
Answer:
x = A cos (w \sqrt{2y_{o}/g})
a) maximun Ф= \sqrt{\frac{2}{3} \frac{2 y_{o} }{g} }
b) minimun Ф = [tex]\frac{\pi }{2}[/tex] - \sqrt{\frac{2}{3} \frac{2 y_{o} }{g} }
Explanation:
For this exercise let's use kinematics to find the time it takes for the mass to reach the floor
y = y₀ + v₀ t - ½ g t²
as the mass is released from rest, its initial velocity is zero (vo = 0) and its height upon reaching the ground is zero (y = 0)
0 = y₀ - ½ g t²
t = [tex]\sqrt{2y_{o}/g}[/tex]
The bucket-spring system has a simple harmonic motion, which is described by
x = A cos wt
in this expression we assumed that the phase constant (Ф) is zero
let's replace the time
x = A cos (w \sqrt{2y_{o}/g})
this is the distance where the system must be for the mass to fall into it.
a) The new system has a total mass of m ’= 3.0 kg, so its angular velocity changes
w = [tex]\sqrt{k/m}[/tex]
In the initial state
w = \sqrt{k/2}
When the mass changes
w ’= \sqrt{k/3}
the displacement in each case is
x = A cos (wt)
for the new case
x ’= A cos (w’t + Ф)
the phase constant is included to take into account possible changes due to the collision of the mass.
we see that this maximum expressions when the cosine is maximum
cos (w´t + Ф) = 1
w’t + Ф = 0
Ф = -w ’t
Ф = - [tex]\sqrt{k/3}[/tex] [tex]\sqrt{2y_{o}/g}[/tex]
\sqrt{\frac{2}{3} \frac{2 y_{o} }{g} }
b) the function is minimun if
cos (w’t + fi) = 0
w’t + Ф = π / 2
Ф = π / 2 - w ’t
Ф = [tex]\frac{\pi }{2}[/tex] - \sqrt{\frac{2}{3} \frac{2 y_{o} }{g} }
vector of magnitude 15 is added to a vector of magnitude 25. The magnitude of this sum
might be:
A. Zero
B.5
C.9
0 15
E.4
and how ?
Explanation:
Given that,
Magnitude of vector A, |A| = 15
Magnitude of vector B, |B| = 25
We need to find the magnitude of this sum.
The maximum sum of the resultant vector,
[tex]R_{max}=|A_1|+|A_2|\\\\=15+25\\\\=45[/tex]
The minimum sum of the resultant vector,
[tex]R_{min}=|A_1|-|A_2|\\\\=15-25\\\\=-10[/tex]
So, the magnitude of this sum either 45 or -10.
if an atom was a scale, in which the nucleus is the size of an apple the electron.....
Answer:
the nucleus is the size of an apple, approximately 5 cm of radius e, the atom has a radius of R = 5 cm 104 = 50000 cm = 50 km
Explanation:
In the Rutherford experiments it was proved that the atomic nucleus has the volume 10-4 the volume of the atom.
If we make a scale design in which the nucleus is the size of an apple, approximately 5 cm of radius e, the atom has a radius of R = 5 cm 104 = 50000 cm = 50 km
This shows that almost the entire volume of the atom is empty.
b) A satellite with mass m orbits the Earth at a radius r. A second satellite also with mass m orbits the
Earth at twice the radius.
How does the force of Earth's gravity acting on the two satellites
compare? PLEASE HURRY
Answer:
So, given the eqn Fg=G(m1+m2/r^2) where G is the gravitational constant, m is the mass of the satellite and m2 is the mass of the earth and r is the distance from earth to the satellite, the force of earths gravity should be quartered.
Cause (2r)^2 gets turned into (4r^2) where 4r^2 is compared to r^2
Explanation:
A spiral spring of 8cm extended to 9.2cm when a load of 1.6N is applied. what is the force constant of the spring, provided the elastic is not exceeded.
Explanation:
By Hooke's Law, Fe = kx.
Since Fe = 1.6N and x = 9.2cm - 8cm = 1.2cm,
k = Fe/x = 1.6N/1.2cm = 1.33N/cm.
Using a scale of 1 cm to represent 10 N, find the size and direction of the resultant of forces of 50 N
and 30 N acting at the angle of 45 O to each other.
Answer:
[tex]74.31\ \text{N}[/tex]
[tex]16.59^{\circ}[/tex]
Explanation:
P = 50 N
Q = 30 N
[tex]\theta[/tex] = Angle between the vectors = [tex]45^{\circ}[/tex]
Resultant is given by
[tex]R=\sqrt{P^2+Q^2+2PQ\cos\theta}\\\Rightarrow R=\sqrt{50^2+30^2+2\times 50\times 30\times \cos45^{\circ}}\\\Rightarrow R=74.31\ \text{N}[/tex]
Angle of resultant
[tex]\phi=\tan^{-1}\dfrac{Q\sin\theta}{P+Q\cos\theta}\\\Rightarrow \phi=\tan^{-1}\dfrac{30\times \sin45^{\circ}}{50+30\cos45^{\circ}}\\\Rightarrow \phi=16.59^{\circ}[/tex]
Magnitude of the resultant is [tex]74.31\ \text{N}[/tex]
Direction of the resultant is [tex]16.59^{\circ}[/tex]
2) Two railway tracks are parallel to west east direction. Along one track, train A moves with a speed of 45 m/s from
west to east, while along the second track, train B moves with a speed of 60 m/s from east to west calculate speed of
Bw.rt. A
Answer:
[tex]Relative\ Velocity = 105m/s[/tex]
Explanation:
Given
[tex]V_A = 45m/s[/tex]
[tex]V_B = 60m/s[/tex]
Required
Determine the speed of B w.r.t A
The question implies that, we determine the relative velocity of B w.r.t A
Because both trains are moving towards one another, the required velocity is a [tex]sum\ of\ velocities\ of[/tex] both trains:
This is shown below:
[tex]Relative\ Velocity = V_A + V_B[/tex]
[tex]Relative\ Velocity = 45m/s + 60m/s[/tex]
[tex]Relative\ Velocity = 105m/s[/tex]
types of magnetic resonance image
Answer: ur mom
Explanation:
A street bridge is 5.5m long if the linear expansion of steel is 0.00001 oc How much will it expand when temperatures is by 10oc? Give answer in Cm
Answer:
[tex]l_o=550.055\ cm[/tex]
Explanation:
Given that,
Length of a street bridge, l = 5.5 m
The coefficient of bridge, [tex]\alpha =0.00001 ^0 C[/tex]
We need to find how much will it expand when temperatures is by 10°C.
The change in length per unit original length is given by :
[tex]\dfrac{\Delta l}{l}=\alpha \Delta T\\\\\Delta l = l\alpha \Delta T\\\\=5.5\times 0.00001 \times 10\\\\\Delta l=0.00055\\\\(l_o-l)=0.00055\\\\l_o=0.00055+5.5\\\\=5.50055\ m\\\\l_o=550.055\ cm[/tex]
Hence, the length will expanded 550.055 cm.
A little girl pushes a 5.0 kg toy baby stroller at constant speed 7.0 m across the floor. She pushes on the handle with a force of 40 N at an angle of 30o with the horizontal. All parts are 4 points each.
Complete Question
1 a A little girl pushes a 5.0 kg toy baby stroller at constant speed 7.0 m across the floor. She pushes on the handle with a force of 40 N at an angle of 30o with the horizontal. How much work is done by the girl on the wagon?
1b A farmhand pushes 20 ㎏ bale of hay 4m across the floor of the barn if she exerts a horizontal force of 60 N on the hay, how much work is done? (5 pts)
All parts are 4 points each
Answer:
1a
[tex]W = 242.5 \ J[/tex]
1b
[tex]W = 240 \ J[/tex]
Explanation:
Considering question a
From the question we are told that
The mass of the toy baby stroller is [tex]m = 5.0 \ kg[/tex]
The distance covered is [tex]d = 7.0\ m[/tex]
The force the girl applies on the handle is [tex]F = 40 \ N[/tex]
The angle at which this force is applied is [tex]\theta = 30^o[/tex]
Generally the workdone is mathematically represented as
[tex]W = F_x * d[/tex]
Here [tex]F_x[/tex] is the force along the horizontal axis , this is mathematically represented as
[tex]F_x = F cos (\theta )[/tex]
=> [tex]F_x = 40 * cos(30 )[/tex]
=> [tex]F_x = 34.64 \ N[/tex]
So
[tex]W = 34.64 * 7[/tex]
=> [tex]W = 242.5 \ J[/tex]
Considering question b
From the question we are told that
The mass of the toy baby stroller is [tex]m = 20 \ kg[/tex]
The distance covered is [tex]d = 4 \ m[/tex]
The force the girl applies on the handle is [tex]F = 60 \ N[/tex]
Generally the workdone is mathematically represented as
[tex]W = F * d[/tex]
=> [tex]W = 60 * 4[/tex]
=> [tex]W = 240 \ J[/tex]