Two uniform bars of the same dimensions are constructed from the same material. One bar has five evenly spaced holes through it and the second bar has only two holes. In these cases, the bars are slid over vertical pegs and rest on a horizontal surface, where friction between the bar and the surface is negligible. The two bars are each pulled by
horizontal forces of equal magnitude F from their right end as shown above. The bars' resulting angular accelerations are recorded.
Is the magnitude of the initial angular acceleration of the bar in case 1 larger than, smaller than or equal to the magnitude of the initial angular acceleration of the bar in Case 2? Explain your reasoning.
Answers
Solution :
The angular acceleration, [tex]$\alpha$[/tex] is obtained from the equation of the [tex]$\text{Newton's second law}$[/tex] of rotational motion,
Thus,
[tex]$\tau = F \times d$[/tex]
or [tex]$\tau = I \times \alpha$[/tex]
where [tex]$\tau$[/tex] is torque, F is force, d is moment arm distance, I is the moment of inertia
Thus, [tex]$\alpha=\frac{(F\times d)}{I}$[/tex]
Now if the force and the moment arm distance are constant, then the [tex]\text{angular acceleration is inversely proportional to the moment of inertia.}[/tex]
That is when, F = d = constant, then [tex]$\alpha \propto \frac{1}{I}$[/tex] .
Thus, moment of inertia, I is proportional to mass of the bar.
The mass is less for the bar in case (1) in comparison with that with the bar in case (2) due to the holes that is made in the bar.
Therefore, the bar in case (1), has less moment of inertia and a greater angular acceleration.
Related Questions
a) How much electrical energy, in joules, does a 1000W space heater consume when it runs for 8h? (b) How much energy is that in kilowatt hours? (c) Calculate the cost of using this heater if 1kWh costs 0.5 dollars.
Answers
Answer:
a. Energy = 28800000 Joules
b. Energy = 8 Kwh
c. Cost = $4
Explanation:
Given the following data;
Power = 1000 Watts
Time = 8 hours
Cost = $0.5 per KWh
Conversion:
1 hour = 60 * 60 = 3600 seconds
8 hour = 8 * 3600 = 28800 seconds
a. To find much electrical energy, in joules;
Energy = power * time
Energy = 1000 * 28800
Energy = 28800000 Joules
b. To find how much energy is that in kilowatt hours;
Energy = power * time
Energy = 1000 * 8
Energy = 8000 Watt-hour = 8000/1000 = 8 Kwh (1 Kilowatts is equal to 1000 watts).
c. To calculate the cost of using this heater;
Cost = 8 * 0.5
Cost = $4
dimension of radius of sphere
Answers
Answer:
The dimension is L
Explanation:
Dimension analysis is a method of representing quantities majorly with respect to some fundamental quantities of mass (M), length (L), time (T).
A sphere has a definite volume which relates to its radius by:
V = [tex]\frac{4}{3}[/tex][tex]\pi[/tex][tex]r^{3}[/tex]
In this equation [tex]\pi[/tex] is a dimensionless quantity, and the unit of v is [tex]m^{3}[/tex].
But, metre is a measure of length, thus it has a dimension of L.
So that,
[tex]m^{3}[/tex] ≅ [tex]L^{3}[/tex]
Then,
[tex]L^{3}[/tex] = [tex]r^{3}[/tex]
Find the cube root of both sides to have,
r = L
Therefore, the dimension of the radius of a sphere is L.
5)
A 2.0-meter length of copper wire is connected across a potential difference of 24 millivolts.
The current through the wire is 0.40 ampere. The same copper wire at the same temperature
Is then connected across a potential difference of 48 millivolts. The current through the wire
is
A)
0.20 A
B)
0.80 A
C)
1.6 A
D)
0.40 A
Answers
Answer:
The current through the wire is equal to 0.8 A.
Explanation:
Given that,
The length of a copper wire = 2 m
Potential difference = 24 mV
The current through the wire is 0.40 A.
The new potential difference is 48 mV.
We need to find the current through the wire.
As the potential difference is doubled for second wire. So the new current will be :
I' = 2I
= 2 × 0.4
= 0.80 A
So, the current through the wire is equal to 0.8 A.
True or false please help I’ll give brainliest
Answers
Answer:
All of them are false
Explanation:
4. electrons flow from earth to the object
5. electrons move freely
6. protons can't move
Answer:
They all false
Aiden is writing a report about the structure of the atom. In her report, she says that the atom has three main parts and two subatomic particles. Do you agree with her? Why or why not?
Answers
Answer:
I don't agree
Explanation:
Atoms have 3 subatomic particles protons, electrons and neutrons,
Which of the following statements is incorrect?
1) A ray of light travels from a point A to point B in a path that takes the shortest time
2) In reflection angle of incidence equal to angle of reflection
3) Magnification for a plane mirror is always unity
4) A plane mirror can form only virtual images
Answers
Answer:
2
Explanation:
in reflection the incident ray and reflected rays are equal an angle
The Statue of Liberty is made of Copper that has turned on Says has WAGNE Bongo Wantse
said about this change?
The change is a physical change because the owner in the same is still there,
The change is a physical change beave a new chemical is was on the outside of the sale,
The change is not a physical change beans the plos at the stanje na dana),
The change is nga physical change because a new chemical istmes on the outside of the stalye
Answers
Complete Question:
The Statue of Liberty is made of copper that has turned green because it has undergone a change. What can be said about this change?
Group of answer choices.
A. The change is a physical change because the copper in the statue is still there.
B. The change is a physical change because a new chemical is formed on the outside of the statue.
C. The change is not a physical change because the color of the statue has changed.
D. The change is not a physical change because a new chemical is formed on the outside of the statue.
Answer:
D. The change is not a physical change because a new chemical is formed on the outside of the statue.
Explanation:
A physical change can be defined as a type of change that only affects the physical form of a chemical substance (matter) without having any effect on its chemical properties. Thus, a physical change would only affect the physical appearance and properties of a chemical substance (matter) but not its chemical properties.
This ultimately implies that, a physical change result in a change of matter from one form or phase (liquid, solid or gas) to another without a corresponding change in chemical composition.
Additionally, a physical change is a type of change that involves an increase or decrease in the volume of a physical object (object). Also, this change can be reversed to the original state under certain conditions.
Since the Statue of Liberty which is made of copper turned green, the change is not a physical change because a new chemical is formed on the outside of the statue.
a car travelled at 50km/hr for 3 hours, how far did the car travel
Answers
Answer:
The answer answer is 150 km
Answer:
Explanation:
Distance =Speed×time
Speed=50km/hr
Time=3hours
Hence the Distance will be(50km/hr×3hours)
The answer is 150km
rocks from volcanoes are used by scientists to study the interior of the earth
TRUE OR FALSE
Answers
I had a carved lava rock necklace when I was a kid & lived in Hawaii. My sister & I developed a rash from wearing the lava rock pendant. We think it was because there was a high level of sulfur in the lava rock.
If you have ever been near an active volcano, the smoke/ steam gives off a smell of sulfur, which smells like rotten
Give atleast (5) etypes of cleaning tools , equipment,supplies, and materials that you can find either in your home or school. Identify each use
Answers
Answer and Explanation:
Cleaning tools, equipment, supplies, and materials that can be easily found in a school in one each are: scrub brush, sponges, buckets and brooms.
These equipments are essential to promote a clean, organized and safe environment and for this reason, they can be easily found both at school and in a home, since the cleanliness of these two places is essential for the well-being, proactivity and health of the people who attend them.
describe 2 ways you could increase the efficiency of a household central heating system
Answers
Answer:
Arrange an annual service. Treat your boiler like your car. ...
Keep your boiler clean. ...
Bleed your radiators. ...
Top up the pressure. ...
Use a Powerflush. ...
Insulate your pipes. ...
Turn the heating on. ...
If all else fails…
Explanation:
15. You are watching a baseball game on television that 15
being broadcast from 4500 km away. The batter hits
the ball with a loud "crack" of the bat. A microphone
is located 22 m from the batter, and you are 2.0 m from
the television set. On a day when sound travels 343 m/s
in air, what is the minimum time it takes for you to hear
the crack of the bat after the batter hits the ball?
Answers
Answer:
t_total = 6.99 s
Explanation:
It asks us how long it takes to hear the sound, for this we must look for the time (t₁) it takes for the sound to reach the microphone, the time it takes for the video signal (t₂) to reach the television and the time (₃) it takes for the TV sound to reach us, so the total delay time is
t_total = t₁ + t₂ + t₂
we look for t1, it indicates that the distance x = 22m
v = x / t
t = x / v
t₁ = 22/343
t₁ = 6.41 10-2 s
time t₂
t₂ = 4500 103/3 108
t₂ = 1.5 10-5 s
time t₃
t₃ = 2/343
t₃ = 5.83 10⁻³
Total time is
t_total = t₁ + t₂ + t₃
t_total = 6.41 10⁻² + 1.5 10⁻⁵ + 0.583 10⁻²
t_total = 6.99 s
Activity 1 MATCH IT
Directions: Match Column A to Column B. Write your answer on the space provided before the number.
COLUMN A
__1. Hiking
__2. Orienteering
__3. Zumba
__4. Volleyball
__5.badminton
COLUMN B
A. It is an outdoor navigational recreational activity using specially drawn and detailed maps.
B. Created through on-the –spot aerobics class using the non- traditional music.
C.Going on an extended walk for the purpose of pleasure and exercise.
D. Can be traced from the ingenuity of William J. Morgan in 1895 at Holyoke Massachusetts.
E. Games are held inside the gym to avoid the effect of air in the flight of the shuttle.
Answers
Answer:
1. A hiking
2. C
3. B
4. D
5. E
Amigos necesito que me ayuden a resolver esta gráfica :').
Answers
Answer:
ANO BA TO?(;-;)
Explanation:
miss the rage??
Hai tiếp điểm hình trụ bằng đồng có đầu hình cầu bán kính R = 70mm, lực ép tiếp điểm F = 100N, Mô đun đàn hồi của đồng là 11.8 * 106(N/cm2). Cho biết: a = 0.86 * (F*R/E)1/3, điện trở suất của đồng là 1.62 * 10-8 (Ω/m), với tiếp điểm đồng thì hệ số K1 = 3,16.10-4 (ΩN1/2). Biết các giá trị ứng suất của đồng là: σdh = 38300 N/cm2; σdẻo = 45000 N/cm2; σd.Nát = 51000 N/cm2. Tính điện trở tiếp xúc trong trường hợp thỏa mãn điều kiện tản dòng lí tưởng và trong trường hợp thực nghiệm.
Answers
Answer:
5dhydydyeze6ese6z7zuezuze6ezyezyezzeze
A car takes a full round of journey in a roundabout with constant speed, as the driver got confused with the route. Can we consider it as a uniform motion? Why?
Answers
Answer: The given statement is True
Explanation:
A uniform motion is defined as the motion where an object is moving at a constant speed.
A non-uniform motion is defined as the motion where an object keeps changing its position and does not move at a constant speed.
We are given:
A car takes a full round of journey in a roundabout with constant speed
As the speed remains constant in a circular path, it is considered a uniform motion.
Hence, the given statement is True
A student connects a small solar panel to a 40 a resistor to make a simple circuit. The solar panel produces a voltage of 2 0.
a Calculate the current in the student's circuit.
Answers
Ohm's law states that :
[tex]v = ir[/tex]the terms used are :
[tex]r = resistance[/tex][tex]v = potential \: \: difference[/tex][tex]i = current[/tex]let's solve for electric current :
[tex]2 = i \times 40[/tex][tex]i = \dfrac{2}{40} [/tex][tex]i = 0.05 \: A[/tex][tex]i = 50 \: mA[/tex][tex]\mathfrak{good\: \: luck \: \: for \: \: your \: \: assignment}[/tex]
Our galaxy, the ______________, contains more than 200 billion stars.
Answers
Answer: Milky Way
Explanation:
Which of the following are correct statements about the way an atom is put
together?
Check all that apply.
A. The valence shell is the innermost shell of electrons in an atom.
B. Electrons are found in the nucleus of an atom.
O C. There are two electrons in all electron shells.
O D. Electrons are in layers around the nucleus.
***** multiple choice ******
Answers
Answer:
valenc e shell
Explanation:
Which of the following graph is used for determining the instantaneous velocity from the slope?
A. distance-time graph
B. x - t graph
C. both of these
D. none of these
Answers
Answer:
B. x - t graph
Explanation:
A position-time (x-t) graph is a graph of the position of an object against (versus) time.
Generally, the slope of the line of a position-time (x-t) graph is typically used to determine or calculate the velocity of an object.
An instantaneous velocity can be defined as the rate of change in position of an object in motion for a short-specified interval of time. Thus, an instantaneous velocity is a quantity that can be found by measuring the slope of a line that is tangent to a point on the graph.
Hence, the x - t graph also referred to as the position-time graph is used for determining the instantaneous velocity from the slope.
For example;
Given that the equation of motion is S(t) = 4t² + 2t + 10. Find the instantaneous velocity at t = 5 seconds.
Solution.
[tex] S(t) = 4t^{2} + 2t + 10[/tex]
Differentiating the equation, we have;
[tex] S(t) = 8t + 2 [/tex]
Substituting the value of "t" into the equation, we have;
[tex] S(5) = 8(5) + 2 [/tex]
[tex] S(5) = 40 + 2 [/tex]
S(5) = 42 m/s.
Answer:
B. x - t graph
Explanation:
Thus, an instantaneous velocity is a quantity that can be found by measuring the slope of a line that is tangent to a point on the graph. Hence, the x - t graph also referred to as the position-time graph is used for determining the instantaneous velocity from the slope.
Two particles, with identical positive charges and a separation of 2.65 10-2 m, are released from rest. Immediately after the release, particle 1 has an acceleration 1 whose magnitude is 5.00 103 m/s2, while particle 2 has an acceleration 2 whose magnitude is 7.70 103 m/s2. Particle 1 has a mass of 6.20 10-6 kg. (a) Find the charge on each particle. q1 = C q2 = C (b) Find the mass of particle 2. kg
Answers
Answer:
a) [tex]q=4.92*10^{-8} C[/tex]
b) [tex]m=4.026*10^{-6} kg[/tex]
Explanation:
From the question we are told that:
Separation distance [tex]d=2.65*10^{-2} m[/tex]
Acceleration 1 [tex]a_1=5.00*10^3 m/s^2,[/tex]
Acceleration 2 [tex]a_2=7.70*10^3 m/s^2,[/tex]
Mass 1 [tex]m_1=6.20*10^{-6}[/tex]
Generally the equation for Force is mathematically given by
[tex]F=ma[/tex]
For Particle 1
[tex]F=6.2*10^{-6} *5*10^3[/tex]
[tex]F=0.031 N[/tex]
Also
[tex]F=\frac{kq_1*q2}{r^2}[/tex]
Where
[tex]q_1=q_2[/tex]
Therefore
[tex]0.031=\frac{9*10^9*q^2}{(2.65*10^-2)^2}[/tex]
[tex]q=4.92*10^{-8} C[/tex]
b)
Generally the equation for Force is mathematically given by
[tex]F=ma[/tex]
[tex]0.031=7.7*10^3[/tex]
[tex]m=4.026*10^{-6} kg[/tex]
The hull of a sunken boat, laying on the seabed, is 9 m below the surface of the sea, where the sea water has an average density of 1,025 kg/m3. The hull’s surface area is 12 m2. What is the total force exerted by seawater on the hull?Required to answer. Single line text.
Answers
Answer:
1084860 N
Explanation:
Applying,
P = ρgh................ Equation 1
Where P = pressure, ρ = density, h = height, g = acceleration due to gravity.
From the question,
Given: ρ = 1025 kg/m³, h = 9 m
Constant: g = 9.8 m/s²
Substitute these values into equation 1
P = (1025)(9)(9.8)
P = 90405 N/m²
Also,
P = F/A.............. Equation 2
Where, F = Force, A = Area.
Make F the subject of the equation
F = PA............... Equation 2
Given: A = 12m²
F = 12(90405)
F = 1084860 N
hey what is magnetic field
Answers
Answer:
a region around a magnetic material or a moving electric charge within which the force of magnetism acts.
Explanation:
The definition of a magnetic field is a place in space near a magnet or an electric current where a physical field is created from a moving electric charge that creates a force on another moving electric charge. An example of a magnetic field is the Earth's magnetic field.
Question 3 of 5
Which term refers to a transfer of thermal energy between objects?
O A. Temperature
OB. Heat
O C. Kinetic energy
O D. Potential energy
Answers
Answer:
Heat
Explanation:
The term heat refers to the conduction process which occurs when energy is passed between objects
Answer
Heat
did quiz and got it correct
Which best compares radiation and conduction?
C Both transfer thermal energy from warm objects to cooler objects.
O Both can transfer energy through empty space.
O Both transfer thermal energy by electromagnetic waves.
O Both involve the transfer of energy through direct contact.
Answers
Answer:
The statements that best compares radiation and conduction are the following: both transfer thermal energy from warm objects to cooler objects and both can transfer energy through matter. The difference is that conduction is through direct heat transfer; whereas, radiation transfers heat through waves.
HELP
What is the momentum of a 50-kg ice skater gliding across the ice at a speed of 5 m/s?
Answers
Answer:
250 kgm/s
Explanation:
To calculate momentum, simply take the product of the mass and velocity.
a body of mass 5kg moving on a horizontal ground has a coefficient of friction 0.36.find the normal reaction acting on the body?
Answers
Answer:
50 N.
Explanation:
From the question given above, the following data were obtained:
Mass (m) = 5 Kg
Coefficient of friction (μ) = 0.36
Normal reaction (N) =?
Next, we shall determine the weight of the body. This can be obtained as follow:
Mass (m) = 5 Kg
Acceleration due to gravity (g) = 10 m/s²
Weight (W) =?
W = mg
W = 5 × 10
W = 50 N
Finally, we shall determine the normal reaction. This can be obtained as follow:
Weight (W) = 50 N
Normal reaction (N) =?
Normal reaction = weight of the body
N = W = 50 N
Thus, the normal reaction acting on the body is 50 N
The isotope used to remove cancer malignancy cell the given options are a. Strontium 89 b. Uranium 238 c. Carbon 14 d. Chlorine 37.......... can anyone tell me the ans plzz
Answers
Answer:
B. Uranium 238.
Explanation:
It is radioactive and can be used to treat cancer in the form of radiotherapy
If a driver makes contact with a steering wheel during a 35 mph crash, she comes to rest in about Δ=15 ms. If, during an identical crash, the driver makes contact with an air bag, she comes to rest in about Δ=110 ms. What is the ratio of the force exerted by the steering wheel to the force exerted by the air bag on the driver?
Answers
Answer:
The ratio of forces is 22 : 3.
Explanation:
Case I:
initial velocity, u = 35 mph
final velocity, v = 0
time, t = 15 ms
Case II:
initial velocity, u = 35 mph
final velocity, v = 0
time, t' = 110 ms
let the mass is m.
According to the Newton's second law, the force is given by the rate of change of momentum.
So
[tex]F =\frac{m(v-u)}{t}\\\\F'= \frac{m(v-u)}{t'}\\\\So, \frac{F}{F'} =\frac{t'}{t}\\\\\frac{F}{F'}=\frac{110}{15}=22:3[/tex]
A 52 kg child on a swing is travelling at 6 m/s . What is his gravitational potential energy if he has 1000 J of the mechanical energy?
Answers
Answer:
The correct answer is "64 J".
Explanation:
The given values are:
Mass,
m = 52 kg
Velocity,
v = 6 m/s
Mechanical energy,
= 1000 J
Now,
The gravitational potential energy will be:
⇒ [tex]P.E=1000-\frac{1}{2}mv^2[/tex]
[tex]=1000-\frac{1}{2}\times 52\times (6)^2[/tex]
[tex]=1000-26\times 36[/tex]
[tex]=1000-936[/tex]
[tex]=64 \ J[/tex]
