Solution :
The distance between the starting point and the end point, [tex]L_0[/tex] = 10 light years
But due to the relativistic motion of Bob and Charlie, the distance will be reduced following the Lorentz contraction. The contracted length will be different since they are moving with different speeds.
For Bob,
Speed of Bob's rocket with respect to Alice, [tex]L_b = 0.7 \ c[/tex]
So the distance appeared to Bob due to the length contraction,
[tex]$L_b=L_0\sqrt{1-\frac{V_b^2}{c^2}$[/tex]
[tex]$L_b=10\times \sqrt{1-0.49} \ Ly$[/tex]
[tex]$=7.1 \ Ly$[/tex]
Therefore, the time required to finish the race by Bob is
[tex]$t_b = \frac{L_b}{V_b}$[/tex]
[tex]$=\frac{7.1 \ c}{0.7 \ c}$[/tex]
= 10.143 year
For Charlie,
Speed of Charlie's rocket with respect to Alice, [tex]L_c = 0.866 \ c[/tex]
So the distance appeared to Charlie due to the length contraction,
[tex]$L_b=L_0\sqrt{1-\frac{V_c^2}{c^2}$[/tex]
[tex]$L_b=10\times \sqrt{1-0.75} \ Ly$[/tex]
[tex]$=5 \ Ly$[/tex]
The time required to finish the race by Charlie is
[tex]$t_b = \frac{L_c}{V_c}$[/tex]
[tex]$=\frac{5 \ c}{0.866 \ c}$[/tex]
= 5.77 year
Baseball runner with a mass of 70kg, moving at 2.7m/s and collides head-on into a shortstop with a mass of 85kg and a velocity of 1.6m/s. What will be the resultant velocity of the system when they make contact with each other
Answer:
The speed of the combined mass after the collision is 2.1 m/s.
Explanation:
mass of runner, m = 70 kg
speed of runner, u = 2.7 m/s
mass of shortstop, m' = 85 kg
speed of shortstop, u' = 1.6 m/s
Let the velocity of combined system is v.
Use conservation of momentum
Momentum before collision = momentum after collision
m u + m' u' = (m + m') v
70 x 2.7 + 85 x 1.6 = (70 + 85) v
189 + 136 = 155 v
v = 2.1 m/s
what is the meanjng of laritude ??
I’m assuming you meant latitude:
The angular distance north or south of the earth's equator, measured in degrees along a meridian, as on a map or globe.
a region based on its distance to the equator uses latitude measurements
basically: up and down , north to south from a certain point
A major artery with a 1.3 cm^2 cross-sectional area branches into 18 smaller arteries, each with an average cross-sectional area of 0.6 cm^2. By what factor is the average velocity of the blood reduced when it passes into these branches?
Answer:
When the blood passes into the smaller branches, its average velocity reduces by a factor of 0.12
Explanation:
Given;
initial area of the artery, A₁ = 1.3 cm²
Area of each smaller 18 arteries, a₂ = 0.6 cm²
Total area of the smaller 18 arteries, A₂ = 18 x 0.6 cm²
Apply flow rate equation;
Q = AV
where;
Q is the flow rate of the blood
V is the average velocity of the blood
If the flow rate is constant, then;
A₁V₁ = A₂V₂
[tex]V_2 = \frac{A_1V_1}{A_2} = \frac{1.3\times V_1}{18\times 0.6} \\\\V_2 = 0.12 \ V_1[/tex]
When the blood passes into the smaller branches, its average velocity reduces by a factor of 0.12
Falls often cause injuries, so one of the significant aspects of falls is the displacement and motion of a body. It is defined as how far a body moves vertically during the fall. Accordingly, there are three important factors that should be known to compute the kinetic energy (KE) of a falling body. These factors are:
Answer:
We need, mass, gravity and height.
Explanation:
When a body falls freely from a height, its initial velocity is zero, but due to the height it has some potential energy at the top and the kinetic energy is zero.
As it falls, the potential energy is gradually converted in to the kinetic energy so that the total energy of the falling body is conserved.
At the time as the body strikes the ground, the entire potential energy is converted into the kinetic energy.
Potential energy is given by
U = m g h
where, m is the mass, g is the gravity and h is the height,
So, to get the kinetic energy we require mass, gravity and height of the body.
Magnetic fields can affect... (Check all that apply)
A. ...the motion of electrically charged particles.
B. ...the acceleration of small objects with mass.
C. ...the speed of light near the magnetic field.
D. ...the date we begin daylight savings time.
E. ...the direction compass needles point.
F. ...the electric current in nearby wires.
Answer:
A. the motion of electrically charged particles
You use a force sensor to measure the weight of an object 10 times, and get the following values: 2.8, 2.6, 2.9, 3.1, 2.4, 2.9, 3.2, 2.5, 2.7, 3.0, where all ten values are in units of N. What is the mean weight of the object, as well as the measurement uncertainty of the weight?
Answer: Mean weight = 2.81 N and Measurement of uncertainty = 0.82 N
Explanation:
Mean = [tex]\dfrac{\text{Sum of observations}}{\text{number of observations}}[/tex]
Mean weight is [tex]($\mu)=\frac{2.8+2.6+2.9+3.1+2.4+2.9+3.2+2.5+2.7+3.0}{10}[/tex]
[tex]=2.81$[/tex]
[tex]$\sum_{i=1}^{10}\left(x_{i}-\mu\right)^{2}=0.61[/tex]
[tex]$\sigma=\sqrt{\frac{1}{N-1} \sum_{i=1}^{10}\left(x_{i}-\mu\right)^{2}}[/tex]
[tex]=\sqrt{\frac{1}{10-1} 0.61}=0.082$[/tex]
Measurement of uncertainty will be [tex]$\sigma=0.082$[/tex]
hence, Weight [tex]$W=2.81 \pm 0.082 N$[/tex]
Which of the following refers to a force acting toward the center of a circular
motion?
A. Centrifugal force
B. Circular force
C. Central force
D. Centripetal force
Answer:
D. Centripetal Force :)
Phát biểu nào sau đây là SAI?
A. Cường độ điện trường là đại lượng
đặc trưng cho điện trường về phương
diện tác dụng lực.
B. Điện trường tĩnh là điện trường có
cường độ E không đổi tại mọi điểm.
C. Đơn vị đo cường độ điện trường là
vôn trên mét (V/m).
D. Trong môi trường đẳng hướng,
cường độ điện trường giảm lần so với
trong chân không
Answer:
B.
Explanation:
sana makatulong sayo
Given that average speed is distance traveled divided by time, determine the values of m and n when the time it takes a beam of light to get from the Sun to the Earth (in s) is written in scientific notation. Note: the speed of light is approximately 3.0×108 m/s. Enter m and n, separated by commas.
Answer:
[tex]5,2[/tex]
Explanation:
From the question we are told that:
Speed of light [tex]C=3.0×10^8 m/s.[/tex]
Generally the equation for Average Speed is mathematically given by
[tex]V_{avg}=\frac{d}{t}[/tex]
Where
d=Distance between the Earth and the sun
[tex]d=1.5*10^11m[/tex]
Therefore
[tex]t=\frac{d}{V_{avg}}[/tex]
[tex]t=\frac{1.5*10^11m}{3.0×10^8 m/s.}[/tex]
[tex]t=5*10^2s[/tex]
Since m and n is given in the form of
[tex]m*10^n[/tex]
Therefore
[tex]m=5 & n=2[/tex]
[tex]5,2[/tex]
Normal conversation has a sound level of about 60 dB. How many times more intense must a 10,000-Hz sound be compared to a 1000-Hz sound to be perceived as equal to 60 phons of loudness
Answer: A 10,000-Hz sound is 10 times more intense as compared to a 1000-Hz sound to be perceived as equal to 60 phons of loudness.
Explanation:
The formula used is as follows.
[tex]\beta = 10 dB log (\frac{I}{I_{o}})\\60 = 10 dB log (\frac{I}{I_{o}})[/tex]
[tex]I_{o} = 10^{-12}[/tex] normal threshold
The difference is sound level is as follows.
60 - 60 = 0
Hence,
[tex]0 = 10 dB [log (\frac{I_{f}}{I_{o}}) - log (\frac{I_{i}}{I_{o}})]\\log (\frac{1000}{I_{o}}) = log (\frac{10000 x}{I_{o}})\\log (10^{15}) = log (10^{16}x)\\15 = 16 + log x\\log x = 1\\x = 10[/tex]
This means that 10,000 Hz sound is 10 times more intense.
Thus, we can conclude that a 10,000-Hz sound is 10 times more intense as compared to a 1000-Hz sound to be perceived as equal to 60 phons of loudness.
A test charge of -1.4 x 10-7 coulombs experiences a force of 5.4 x 10-1 newtons. Calculate the magnitude of the electric field created by the
negative test charge.
ОА.
1.4 x 106 newtons/coulomb
ОВ.
1.9 x 106 newtons/coulomb
OC. 5.4 x 10-1 newtons/coulomb
OD
3.6 x 106 newtons/coulomb
Answer:
3.86×10⁶ Newton/coulombs
Explaination:
Applying,
E = F/q....................... Equation 1
Where E = Electric Field, F = Force, q = charge.
From the question,
Given: F = 5.4×10⁻¹ N, q = -1.4×10⁻⁷ coulombs
Substitute these values into equation 1
E = 5.4×10⁻¹/ -1.4×10⁻⁷
E = -3.86×10⁶ Newtons/coulombs
Hence the magnitude of the electric field created by the
negative test charge is 3.86×10⁶ Newton/coulombs
Answer the following questions
1. Heat in liquid travels from
a) bottom to top
b) top to bottom
c) left to right
d) right to left
2. The direction of flow of heat is
a) always from a cooler body to a hotter body
b) always from a hotter body to cooler body
c) always from a body at a lower temperature to a body at a higher temperature
d) all the above
3. A cold steel spoon is dipped in a cup of hot milk. The steel spoon transfer the heat to its other end by the process of
a) convection
b) conduction
c) radiation
d) none of the above
On Ramesh’s13th birthday, his father invited all his friends and their relatives. It was a big party with lots of food and DJs. Ramesh didn’t like the loud sound of DJs and asked his father to play it in a low volume so that their neighbours do not get much disturbed and people at the party can also enjoy the music. Ramesh’s father felt good for his wisdom and did as he said.
→Do you think when loud music is played at a party is acceptable to all the people living in, neighbourhood? Give a reason for your answer
→How can you control noise pollution at your end?
How does exhailing remove waste from the body? Explain the systems that make this happen‚ using complete sentences
When we exhale, 90% waste material is Carbon Dioxide ( CO2 ) , so, it gets exhaled out in the form of CO2 rich air and it gets removed from the body, therefore our internal body becomes more pure and helps in making our internal temperature constant at a suitable level.
Match each term to the best description
a. Coefficient of friction
b. Friction
c. Kinetic friction
d. Normal
e. Static friction
1. A force that acts parallel to the surface.
2. A force that acts perpendicular to the surface.
3. A force that increases as applied force increases up to some maximum value
4. Magnitude depends on the interacting materials
5. A force that is constant regardless of the applied force
Answer:
Coefficient of friction = Magnitude depends on the interacting materials
Friction = A force that acts parallel to the surface.
kinetic friction = A force that is constant regardless of the applied force
Normal = A force that acts perpendicular to the surface
Static friction = A force that increases as applied force increases up to some maximum value
Explanation:
Let's define all the forces, and then let's solve the problem.
Normal force:
When an object rests on some place (like a book on the table) the force that causes the book to not fall through the table is called the normal force, which is usually equal to the weight of the object and acts perpendicular to the surface where the object is resting.
Friction force.
When an object moves (or tries to move) parallel to a surface, such that the object is in contact with that surface, there appears a force that opposes to the movement (the force is parallel to the surface, and in the opposite direction to the movement).
And this force can be written as:
F = -N*μ
Where μ is the coefficient of friction and N is the normal force.
If the object is not moving yet (but there is applied a force that would move the object) the coefficient is called the coefficient of static friction which increases in a given range, until it can't keep increasing and the object starts to move, while if the object is moving, the coefficient is called the coefficient of kinetic friction and it is constant, where usually the first one is larger than the second, and these coefficients depend on both materials, the surface one and the object one.
Then we have two friction forces, one called the kinetic friction and the other called the static friction.
Then:
Coefficient of friction = Magnitude depends on the interacting materials
Friction = A force that acts parallel to the surface.
kinetic friction = A force that is constant regardless of the applied force
Normal = A force that acts perpendicular to the surface
Static friction = A force that increases as applied force increases up to some maximum value
Fiber optic (FO) cables are based upon the concept of total internal reflection (TIR), which is achieved when the FO core and cladding have the same refractive indices.
a. True
b. False
Answer:
False
Explanation:
Though fiber active cable is based on the concept of internal reflection but it is achieved by refractive index which transmit data through fast traveling pulses of light. It has a layer of glass and insulating casing called “cladding,”and this is is wrapped around the central fiber thereby causing light to continuously bounce back from the walls of the Cable.
Determine the values of m and n when the following average magnetic field strength of the Earth is written in scientific notation: 0.0000451 T. Enter m and n, separated by commas.
Answer:
B = 4.51×10⁻⁵ T
Explanation:
Given that,
The average magnetic field strength of the Earth is 0.0000451 T.
We need to write the value in the form of scientific notation. Any number in scientific notation is written as follows :
N=a×bⁿ
Where
n is any integer and a is a real no
So,
0.0000451 = 4.51×10⁻⁵ T
So, the required answer is equal to 4.51×10⁻⁵ T.
A pair of butterflies reproduces and has one thousand offspring. All one thousand of the offspring have the alleles Aa. What is the most likely combination of alleles (genotype) for each parent?
Answer:
Alleles AA and aa
Explanation:
For all the offsprings of the butterflies to have the same heterozygous alleles Aa, it means the two parents have different homogyzous alleles. That is, one of the parents had the alleles AA while the other had the alleles aa. Thus, a combination of the two pairs of alleles will produce 100% Aa alleles in the offspring as seen in the image attached.
a car increases its speed as it moves across the floor. which form of energy is increasing for the car?
Answer:
kinetic
Explanation:
i just remember it from last year
Answer:
kinetic energy
Explanation:
expression for kinetic energy is
kinetic energy = (1/2) × mass × (velocity)^2
so , as velocity increases K.E increases
A hot air balloon is moving at a speed of 10 meters/second in the +x direction. The balloonist throws a brass ball with a velocity of -2
meters/second with respect to himself. If the ball lands after 20 seconds, about how far does it land horizontally from the point at which it was
released?
OA 98 meters
OB. 160 meters
OC. 196 meters
OD. 420 meters
Answer:
160 meters
Relative of speed Vr = 10 -2 = 8 m/s (horizontal speed)
20 sec * 8 m/s = 160 m since ball travels 20 sec
Answer:
160 meters
Explanation:
A person places a cup of coffee on the roof of his car while he dashes back into the house for a forgotten item. When he returns to the car, he hops in and takes off with the coffee cup still on the roof.
(a) If the coefficient of static friction between the coffee cup and the roof of the car is 0.24, what is the maximum acceleration the car can have without causing the cup to slide?
(b) What is the smallest amount of time in which the person canaccelerate the car from rest to 13 m/s andstill keep the coffee cup on the roof?
Answer:
(a) The acceleration is 2.35 m/s^2.
(b) The time is 5.53 s.
Explanation:
coefficient of friction = 0.24
(a) The acceleration of the car is
[tex]a =\mu g\\\\a = 0.24 \times9.8\\\\a = 2.35 m/s^2[/tex]
(b) initial velocity, u =0, final velocity, v = 13 m/s
Let the time is t.
Use first equation of motion
v = u + a t
13 = 0 + 2.35 x t
t = 5.53 seconds
The lumberjack pulls on the sled with 40 N at an angle of 30 degrees, pulling so the sled moves at a constant velocity. 1) What is the x component of the applied force? 2) What is the y component of the applied force? 3) If the loaded sled has a mass of 65 kg, what is the magnitude of the force of gravity? 4) What is the magnitude of the normal force acting on the sled? 5) What is the coefficient of friction between the snow and the sled?
1) (40 N) cos(30°) ≈ 34.6 N
2) (40 N) sin(30°) = 20 N
3) (65 kg) g = (65 kg) (9.80 m/s²) = 585 N
4) The net force on the sled acting in the vertical direction is made up of
• the sled's weight, 585 N, pointing downward
• the vertical component of the applied force, 20 N, pointing upward
• the normal force, with magnitude n, also pointing upward
The sled does not move up or down, so by Newton's second law,
∑ F = n + 20 N - 585 N = 0 ==> n = 565 N
5) The net force in the horizontal direction consists of
• the horizontal component of the applied force, 34.6 N, acting in the direction the sled's movement (call this the positive direction)
• kinetic friction, with magnitude f, pointing in the opposite and negative direction
By Newton's second law,
∑ F = 34.6 N - f = 0 ==> f ≈ 34.6 N
Now if µ is the coefficient of kinetic friction, then
f = µn ==> µ = f/n = (34.6 N) / (565 N) ≈ 0.0613
The component of the force is the effective part of that force in that direction.
What is the component of a force?The component of the force is the effective part of that force in that direction.
1) The horizontal component of a force = 40 N cos 30 degrees = 34.6 N
2) The vertical component of the force = 40 N sin 30 degrees = 20 N
3) The magnitude of the gravitational force = mg cos 30 degrees = 65 Kg * 9.8 m/s^2 * cos 30 degrees = 551.7 N
4) The normal force = 551.7 N
5) The coefficient of friction = F/R = 40 N /551.7 N = 0.07
Learn more about component of a force:https://brainly.com/question/15529350
#SPJ6
The volume of a liquid is 830m'at 30°C and it is 850m'at 90°C. The
coefficient of volume expansion of the liquid is
Answer:
4.02×10⁻⁴ K⁻¹
Explanation:
Applying,
γ = (v₂-v₁)/(v₁Δt)................. Equation 1
Where γ = coefficient of volume expansion, v₂ = Final volume, v₁ = initial volume, Δt = change in temperature.
From the question,
Given: v₂ = 850 m³, v₁ = 830 m³, Δt = (90-30) = 60°C
Substitute these values into equation 1
γ = (850-830)/(830×60)
γ = 20/(830×60)
γ = 4.02×10⁻⁴ K⁻¹
A physical system is in the state |α> = cos(α)|+> + sin(α)|->. Two observables  = a(|+><+| + |-><-|) + b(|+><-| + |-><+|) e B = a(|+><+| - |-><-|) are measured. Check the uncertainty relationship for these two operators.
Answer:
sorry dear
Explanation:
sorry dear but ur question is hard to understand can u try to edit it so i can tell u the answer?
Got it never mind. The only reason I'm typing more is to fill out the required space
Answer:
hey. i dont know what you tryna say but if u replying to someone else, you should use the comments section. in that way you won't lose points.
What innovation did jethro wood add to plows in the 1800s?
Built by 1800, it was the home of inventor Jethro Wood (1774-1834), whose 1819 invention of an iron moldboard plow revolutionized American agriculture.
A conductor is placed in an external electrostatic field. The external field is uniform before the conductor is placed within it. The conductor is completely isolated from any source of current or charge.
1. Which of the following describes the electricfield inside this conductor?
a. It is in thesame direction as the original external field.
b. It is in theopposite direction from that of the original externalfield.
c. It has adirection determined entirely by the charge on itssurface.
d. It is alwayszero.
2. The charge density inside theconductor is:
a. 0
b. non-zero;but uniform
c. non-zero;non-uniform
d. infinite
Answer:pp
Explanation:
ii
Convert the following:
1) 367.5 mg = _______ g
2) 367 mL = _______ L
3) 28.59 in =______ cm
4) 8 0z =_______lb
5) 0.671 mm =_____m
Answer:
1) 0.3675
2) 0.367
3) 72.6186
4) 0.5
5) 0.000671
Answer:
1) 367.5 mg = 0.3675 g
2) 367 mL = 0.367 L
3) 28.59 in = 72.61 cm
4) 8 0z = 0.5 lb
5) 0.671 mm = 0.0000671 m
A bullet of mass 0.5 kg is moving horizontally with a speed of 50 m/s when it hits a block of mass 3 kg that is at rest on a horizontal surface with a coefficient of friction of 0.2. After the collision the bullet becomes embedded in the block. How much work is being dne by bullet?
Answer:
Work done by the bullet is 612.26 J.
Explanation:
mass of bullet, m = 0.5 kg
initial velocity of bullet, u = 50 m/s
coefficient of friction = 0.2
mass of block, M = 3 kg
let the final speed of the bullet block system is v.
use conservation of momentum
Momentum of bullet + momentum of block = momentum of bullet block system
0.5 x 50 + 3 x 0 = (3 + 0.5) v
v = 7.14 m/s
let the stopping distance is
The work done is given by change in kinetic energy of bullet
initial kinetic energy of bullet, K = 0.5 x 0.5 x 50 x 50 = 625 J
Final kinetic energy of bullet, K' = 0.5 x 0.5 x 7.14 x 7.14 = 12.74 J
So, the work done by the bullet
W = 625 - 12.74 = 612.26 J
CHEGG A neutron star has a mass of 2.08 × 1030 kg (about the mass of our sun) and a radius of 6.73 × 103 m. Suppose an object falls from rest near the surface of such a star. How fast would it be moving after it had fallen a distance of 0.0093 m? (Assume that the gravitational force is constant over the distance of the fall, and that the star is not rotating.
Let g be the acceleration due to gravity on the surface of the star. By Newton's second law, the gravitational force felt by the object has a magnitude of
F = GMm/r ² = mg
where
• G = 6.67 × 10⁻¹¹ Nm²/kg² is the gravitational constant,
• M = 2.08 × 10³⁰ kg is the mass of the star,
• m is the unknown mass of the object, and
• r = 6.73 × 10³ m is the radius of the star
Solving for g gives
g = GM/r ²
g = (6.67 × 10⁻¹¹ Nm²/kg²) (2.08 × 10³⁰ kg) / (6.73 × 10³ m)²
g ≈ 3.06 × 10¹² m/s²
The object is in free fall with uniform acceleration and starting from rest, so its speed after falling 0.0093 m is v such that
v ² = 2g (0.0093 m)
v = √(2g (0.0093 m))
v ≈ 240,000 m/s ≈ 240 km/s