Answer:
10.44° per sec
Explanation:
Initial angular speed N = 2 rotations per minute
converting to rad/s ω = 2πN/60 = (2 x 3.142 x 2)/60 = 0.21 rad/s
the initial radius of the disk = 16 cm = 0.16 m
final radius = 17 cm = 0.17 m
Angular momentum = [tex]I[/tex]ω
where [tex]I[/tex] = rotational inertia = mass x [tex]radius^{2}[/tex]
ω = angular speed
For the initial case
[tex]I[/tex] = m x [tex]0.16^{2}[/tex] = 0.0256m
Angular momentum = 0.0256m x 0.21 = 0.0054m
For second case
[tex]I[/tex] = m x [tex]0.17^{2}[/tex] = 0.0289m
Angular momentum = 0.0289m x ω = 0.0289mω
For conservation of rotational momentum, initial angular momentum must be equal to the final angular momentum
0.0054m = 0.0289mω
m cancels out, we have
0.0054 = 0.0289ω
ω = 0.187 rad/s
converting back to rpm, we have
N = 0.187/2π = 0.029 rotations per sec
0.029 x 360 = 10.44° per sec
The period of a pendulum is the time it takes the pendulum to swing back and forth once. If the only dimensional quantities that the period depends on are the acceleration of gravity, g, and the length of the pendulum, ℓ, what combination of g and ℓ must the period be proportional to? (Acceleration has SI units of m • s-2.)
Answer: √(L/g)
Explanation:
Here we only work with the units:
The unit of the period is units of time, so we have:
[T] = [s]
Now, the units of the length of the pendulum are units of distance:
[L] = [m]
And the units of the acceleration are:
[g] = [m/s^2]
Now, we want to work with those two in such way that the end result is only in seconds.
First, we can see that in g we have seconds square, so we know that we should use a square root.
Then we can divide L by g in order to remove the distance unit, and to have the time unit in the numerator
[L/g] = [m*s^2/m] = [s^2]
Now we apply the square root:
[√(L/g)] = [√s^2] = [s]
Then the combination is: √(L/g)
T = k*√(L/g)
where k is the constant of proportionality.
3) An earth moving machine uses diesel oil, which when burnt will produce 3.0x10 9 J of energy. The work performed by the machine is 2.7x 10 8 J. What is the efficiency of the machine?
Answer:
The answer is below
Explanation:
The efficiency of a machine is the ratio of its output to its input. The efficiency shows how effective the machine by the way it converts the input energy into work. The higher the efficiency of the machine the more effective it is. The efficiency is usually less than 1.
Given that the machine uses diesel oil (input) that can produce 3.0 x 10⁹ J of energy while the work performed by the machine (output) is 2.7 x 10⁸ J. The efficiency is given as:
Efficiency = output / input = 2.7 x 10⁸ J / 3.0 x 10⁹ J = 0.09 = 9%
This means that the machine is not effective because of its low efficiency
what's the difference between force of gravity and the earth's magnetic field?
Answer:
Gravitational fields are determined only by the mass ( or mass-energy) of a body. ... magnetic fields are produced by charged particles in motion, and depend on the charge and velocity of these particles, but not on their mass. Magnetic fields are 'polar' fields with a North and South polarity.
Explanation:
What is CGS unit of weight
Answer:
[tex] \boxed{dyne}[/tex]Explanation:
The weight of a body is defined as the force with which it is attracted towards the centre of a planet. A spring balance measures it. It's unit is Newton ( N ) in the SI system and dyne in the CGS system.
Hope I helped!
Best regards!
Weight is force.
The CGS unit of force is the dyne.
The SI unit of force is the Newton.
Hi please may someone help me especially on the sketch part.
An object falls from a hovering helicopter and hits the ground at a speed of 30 m/s. How long does it take the object to reach the ground and how far does it fall? Sketch a velocity-time graph for the object (ignore air resistance).
Ignoring the air resistance it will take about 3 seconds for the object to reach the ground.We know that the acceleration due to gravity is 10m/s2.
We also know that the final velocity is 30 m/s while the initial velocity is 0 m/s
we can use the formulae for acceleration to calculate the time taken/
(final - initial velocity)/timetaken=10
(30-0)/timetaken=10
timetaken =30/10=3 seconds
Identifying Energy Transformations
What is one energy transformation that is taking place when a plant is growing?
radiant energy to thermal energy
thermal energy to nuclear energy
O chemical energy to thermal energy
O radiant energy to chemical energy
Answer:
My answer is radiant energy to chemical energy because it uses the sun which is a form of solar energy and then converts the food to chemical energy for the plant itself
Answer: Radiant energy to chemical energy
Explanation: Right on edge2021
The particles of a GAS within a closed container will collide with the container walls, exerting a FORCE. The force per unit of AREA is known as what?
Answer:
Pressure
Explanation:
One of the theories propounded by the Kinetic molecular theory, and which also provides an explanation of the several gas laws, is the statement that the gas molecules in a container, travel in straight lines and are in constant collision with themselves and the walls of the container, thus exerting force. This force is the pressure which is defined as the force per unit area.
There is no loss of energy in the collisions involving the gas molecules and that is why their movement can be described as elastic. The descriptions of the behavior of gas molecules in the Kinetic Molecular Theory, give rise to Charles law, Boyle's Law, Avogadro's Laws, Dalton's Law, and Amonton's Law.
Answer:
The pressure
Explanation:
Molecules of gases are constantly in motion, colliding with the walls of their container. This constant collision impacts force on the walls of the container, which depends on the speed with which the molecules are moving. The speed with which these molecules travel depends on the average kinetic energy of the molecules, which is proportional to the temperature.
This force when exerted per unit area is the pressure the gases exert on the walls of the container.
Select the correct answer. Rita is a registered dietician. What does her work entail? A. prescribing medication for clients B. cooking healthy meals for students C. demonstrating how to use gym equipment D. making recommendations for healthy eating habits
Answer:
D
Explanation:
The answer is D because:
A) Only doctors are allowed to prescribe medications.
B) Rita is not a chef/cook.
C) Rita is not a personal trainer
D) The job of a dietican is to provide reccomendations to their clients in order for them to implement a healthy lifestyle via consuming what is best for them.
Hope this helps :)
Answer:
D.) Making recommendations for healthy eating habits
Explanation: PLATO :)))
Please help me ASAP...
A train increases its speed steadily from 10 m/s to 20 m/s in 1 minute.
a What is its average speed during this time, in m/s?
b How far does it travel while increasing its speed?
Answer:
A: 15 m/s
B: 900 Meters
Explanation:
A. Average speed is equal to final velocity plus initial velocity divided by two
Va= (20+10)/2 = 15 m/s
B.
distance = speed × time
D= 15 m/s * 60s = 900 Meters
Answer:
Answer is in the attachment.
Explanation:
Hope this helps.
Please mark me as Brainliest.
if you ran 15 km/hr for 2.5 hours, how much distance would you cover?
Answer: 37.5 km
Explanation:
The question is that
If you ran 15 km/hr for 2.5 hours, how much distance would you cover ?
Where
Speed = 15 km/ hr
Time = 2.5 hours
Using the formula for speed.
Speed = distance/time
Substitute speed and time into the formula
15 = distance/ 2.5
Make distance the subject of formula by cross multiplying.
Distance = 15 × 2.5
Distance = 37.5 km.
What areas of the work force can science be applied to?
Select all that apply
government regulatlon
healthcare
a telemarketing
environmental engineering
banking
Answer:
All of the work of lifeExplanation:
In all works of life science can be applied, in-fact science has already been applied already, even in the humanities, social sciences and art related studies sciences is being applied,
Furthermore, the application of science and technology knows no boundaries, and as science is advancing day by day, expanding to new frontiers and breaking new limits so is it application to all works of life and relevance everyday.
A stationary siren creates an 894 Hz
sound. When a motorcyclist is driving
toward it, she hears a 926 Hz sound
How fast is she driving?
(Speed of sound = 343 m/s)
(Unit = m/s)
Answer:
12.3 m/s
Explanation:
The Doppler equation describes how sound frequency depends on relative velocities:
fr = fs (c + vr)/(c + vs),
where fr is the frequency heard by the receiver,
fs is the frequency emitted at the source,
c is the speed of sound,
vr is the velocity of the receiver,
and vs is the velocity of the source.
Note: vr is positive if the receiver is moving towards the source, negative if away.
Conversely, vs is positive if the receiver is moving away from the source, and negative if towards.
Given:
fs = 894 Hz
fr = 926 Hz
c = 343 m/s
vs = 0 m/s
Find: vr
926 = 894 (343 + vr) / (343 + 0)
vr = 12.3
The speed of the car is 12.3 m/s.
Which two possible explanations does the video give for why white light changes into colored light? Color is an impurity added to white light by the prism. Color is present in the materials on which white light shines. White light contains seven colors, which are separated by the prism. White light reacts with chemicals in the air to produce seven colors.
Answer:
White light contains seven colors, which are separated by the prism.
White light reacts with chemicals in the air to produce seven colors.
Explanation:
It was first observed by Sir Issac Newton, that when white light is passed through a prism, an elongated, coloured patch of light is obtained on a screen placed behind the prism. The seven colours obtained constitute the spectrum of white light.
In nature, white light is separated into its constituent wavelengths when white light interacts with substances in the atmosphere.
Answer:
The correct answer is “color is an impurity added to white light by the prism.”
and
“White light contains seven colors, which are separated by the prism
Explanation:
A central air-conditioner uses 3500W of electricity. If electricity costs $0.087/kW*h. calculate how much it would cost to operate the air-conditioner 24 hours a day for 4 months (120 days).
Answer:
$876.96
Explanation:
The energy used is:
3500 W × (24 hr/day) × (120 day) × (1 kW / 1000 W) = 10,080 kWh.
So the cost is:
10,080 kWh × ($0.087 / kWh) = $876.96
i)Distinguish between different methods of charging. ii) You are provided with a positively charged gold leaf electroscope. State and explain what happens when a. a glass rod rubbed with silk is brought near the disc of electroscope. b. an ebonite rod rubbed with fur is brought near the disc of electroscope. c. an uncharged metal rod is brought near the disc of electroscope d. a glass rod rubbed with silk is rolled on the disc of electroscope.
Answer:
Explanation:
On rubbing a glass rod with silk, the electrons from the glass rod get transferred to the silk. The silk now has an excess of electrons and so is negatively-charged. On the other hand, the glass rod is deficient in electrons and hence is positively-charged.
In the above case, the silk undergoes negative electrification.
Now, when the positively charged glass rod is touched on the disc of a negatively charged gold leaf electroscope, the electrons shifts towards rod, hence amount of charge on gold leaves decreases and the divergence between the gold leaves decreases as unlike charges attract each other.
Hence, the divergence decreases when a glass rod rubbed with silk is brought near the disc of negatively charged electroscope.
hope it helps pls mark me as brainliest
Match words at the left to the correct blanks in the sentences on the right. Not all words will be used.1. The energy that drives the expansion of a star into a subgiant or red giant comes from HYDROGEN SHELL FUSION2. Stars with mass greater than about 8 solar masses are considered HIGH-MASS STARS3. The final stage of core fusion in a low-mass star is HELIUM FUSION4. Stars that are fusing hydrogen in their cores are MAIN-SEQUENCE STARS5. When it dies, a high-mass star explodes as a SUPERNOVA6. A star that is expanding (into a subgiant and then a giant) has a(n) INERT HELIUM CORE7. When it dies, a low-mass star expels a PLANETARY NEBULA8. Stars with masses less than about two solar masses are considered LOW-MASS STARS
Answer:
In what way is iron unique among the elements?
It has the lowest mass per nuclear particle.
Match words at the left to the correct blanks in the sentences on the right. Not all words will be used.
-The energy that drives the expansion of a star into a subgiant or red giant comes from HYDROGEN SHELL FUSION
-Stars with mass greater than about 8 solar masses are considered HIGH-MASS STARS
-The final stage of core fusion in a low-mass star is HELIUM FUSION
-Stars that are fusing hydrogen in their cores are MAIN-SEQUENCE STARS
-When it dies, a high-mass star explodes as a SUPERNOVA
-A star that is expanding (into a subgiant and then a giant) has a(n) INERT HELIUM CORE
-When it dies, a low-mass star expels a PLANETARY NEBULA
-Stars with masses less than about two solar masses are considered LOW-MASS STARS
Which of the following best describes a consumer?
0. a business owner who sells clothes
0. someone who studies economics
O. a farmer who sells his crops
O. a person who buys goods and services
Answer:
a business who buys goods and services
The radius of a small ball is around 3.79747 cm. The radius of a basketball is about 3.16 times larger. What is the ratio of the surface areas of the small ball and a basketball? 2. What is the ratio of their volumes?
Explanation:
The ratio of the areas is the square of the ratio of the radii.
A/A = 3.16² = 9.99
The ratio of the volumes is the cube of the ratio of the radii.
V/V = 3.16³ = 31.6
Question 1 (2 points)
(01.01 LC)
Which of the following is a characteristic of science? (2 points)
QU
Reproducible by other scientists
Ob
The personal opinion of the scientist
С
Using variable conditions for each test
d
Including only the data that supports a hypothesis
Answer:
Reproducible by other scientists
Explanation:
I just took the test
an object is +2 m from the reference point. the object starts from rest it travels for 3 seconds and has a final position of -16 m. what is the acceleration of the object?
Answer:
Solution
Given:
initial velocity (u)=0m/s (because an object
starts from the rest)
time (t)=3sec
diatance travelled(s)=14m(16-2=14)
acceleration (a)=?
Now,
According to the formula
s=ut+1/2at^2
or,14 =0×3+1/2×a×3^2
or, 14=0+a/2×9
or, 14=9a/2
or, 9a=28
or, a=28/9
or, a=3.1 m/s^2
Therefore, the acceleration of the object is 3.1m/s^2 ans.
What two factors determine how much potential energy an object has?
Answer:
The mass of the object and its height in the gravitational field of the Earth.
Explanation:
If we are talking about gravitational potential energy which is defined as:
[tex]U=m\,*\,g\,*\,h[/tex]
being "m" the object's mass, "g" the acceleration due to gravity, and "h" the height at which the object is located relative to the conventionally picked level for zero of potential energy.
As long as the value of "g" is constant, the only two variables that determine the gravitational potential energy are the mass (m) of the object and its relative height (h).
Answer:
The objects weight and height above Earth's surface
Explanation:
K12 :)
If we removed the producers from this food web, how would it affect the balance of the ecosystem?
In a food web, the removal of any trophic level upsets the balance within the web and can cause its eventual collapse. Because producers capture solar energy and convert it to food energy, their loss would affect every other level of the food web.
Explanation:The removal of the producers would cause the collapse of the entire food web. Primary consumers or herbivores, which feed on producers directly, would die off. The next to be affected would be the secondary consumers or carnivores that eat the primary consumers. Higher level consumers would suffer as organisms from lower trophic levels start to die off. Decomposers would break down the bodies of dead organisms, returning their basic elements and compounds to the environment. However, even these dead organisms would run out and the entire food web would collapse.
Hope you like the answer.
Gravity is affected by the ?
Answer:
Mass and distance
Explanation:
The force of gravity the masses exert on each other. If one of the masses is doubled, the force of gravity between the objects is doubled. increases, the force of gravity decreases. Hence, answer is mass and distance
whats suface tension
Answer: "Surface tension is a film of a liquid caused by the attraction of the particles in the surface layer by the bulk of the liquid, which tends to minimize surface area."
Hope this helps!
Answer:
Explanation:
Surface tension is the property of a liquid surface. It is an effect where the surface of the liquid is strong.
example - small insects can walk on water as they do not have enough weight to penetrate it.
This image might help you
Hope it helps
plz mark as brainliest!!!!!!!
Question 2 of 10
Which of the following is an Sl unit?
A. Foot
B. Inch
C. Meter
D. Mile
SUBMIT
Answer:
C. Meter
Explanation:
The International System of Unit (SI) is gotten from the french word Systeme international is a modern form of metric measurement. It is the system of measurement that is universally accepted. It is from this SI units that all other system of units are derived. There are seven basic SI units which are:
1) Length in Meter (m)
2) Time in Seconds (s)
3) Amount of Substance in mole (m)
4) Electric current in ampere (A)
5) Temperature in kelvin (k)
6) Luminous intensity in candela (cd)
7) Mass in kilogram (kg)
A 1.00-kg glider attached to a spring with a force constant 25.0 N/m oscillates on a frictionless, horizontal air track. At t = 0, the glider is released from rest at x = -2.80 cm (that is, the spring is compressed by 2.80 cm). (a) Find the period of the glider's motion. How does the period depend on the mass and the spring constant? Does it depend on the amplitude of oscillation? s (b) Find the maximum values of its speed and acceleration. speed m/s acceleration m/s2 (c) Find the position, velocity, and acceleration as functions of time. (Where position is in m, velocity is in m/s, acceleration is in m/s2, and t is in s. Use the following as necessary: t.) x(t) = v(t) = a(t) =
Answer:
a) T = 1.26 s , b) v_max = 0.14 m / s , a_max = 0.7 m / s²
c) x = 0.028 cos (5 t) , v = - 0.14 sin 5t, a = - 0.7 cos 5t
Explanation:
This is a simple harmonic motion exercise that is described by the equation
x = A cos (wt +Ф)
with
w = √ (k / m)
let's apply this expression to our case
a) Angular velocity is related to frequency
w = 2π f
frequency and period are related
f = 1 / T
we substitute
2π / T = √ (k / m)
T = 2π √(m / k)
let's calculate
T = 2π √(1/25)
T = 1.26 s
In the expression for the period, the amplitude does not appear, therefore there is no dependence, as long as Hooke's law is fulfilled, which is correct for small amplitudes.
b) in the initial equation we have the position as a function of time, let's use the definition of speed and acceleration
v = dx / dt
v = - A w sin (wt + Ф)
the speed is maximum when the sine is -1
v_max = A w
w = √ (k / m)
w = √ 25/1
w = 5 rad / s
the amplitude of the movement is equal to the maximum compression of the spring
A = 2.8 cm = 0.028 m
we substitute
v_max = 0.028 5
v_max = 0.14 m / s
acceleration
a = dv / dt
a = - A w² cos (wt + Ф)
the acceleration is maximum when the cosine is -1
a_max = A w²
let's calculate
a_max = 0.028 5²
a_max = 0.7 m / s²
c) let's start by finding the phase constant
v = -A w cos (wt + Ф)
at t = 0 they indicate that the system has v = 0
0 = -A w sin (0 + Ф)
Ф = sin⁻¹ 0
Ф = 0
we write the equation
x = 0.028 cos (5 t)
v = - A w sin (wt + Ф)
v = - 0.028 5 sin (5t + 0)
v = - 0.14 sin 5t
acceleration
a = - A w² cos (wt + Ф)
a = - 0.028 5 2 cos (5 t + 0)
a = - 0.7 cos 5t
A machine can never be 100% efficient because some work is always lost due to which factor? friction gravity static input force
Explanation:
Hi,
The answer is friction.
There is almost no machine which are not affected by friction. It losts some work due to friction while working.
Hope it helps..
Answer:
friction
Explanation:
the other options dont effect efficiency
The ways to measure the mass and volume of irregular object
Answer:
When we have irregular objects, it may become very hard to calculate the volume of the object, as we actually can not use any simple equation to find it.
The mass is less tricky, just find a scale and wheight it, now we know the mass of the irregular object.
One way to measure the volume of the object is using water... how we do it?
Get some recipient with water, measure the height of the water.
Introduce your object into the water and totally submerge it, now the level of the water will rise. This is because as you introduce the object under the water, you are displacing up a given volume of water that has the same volume as the irregular object.
Now that you know the height of the water before and after you put your object, you can easily calculate the volume of water displaced, and that will be the volume of the object (the tricky part may be totally submerging the object if, for example, is wood and it floats, here you can use a thin wire to push it down but it will affect a little bit the measures.)
(02.10 LC)
Which American sport stems from a combination of the British sports rugby and soccer?
Baseball
Basketball
Tennis
Football
Question 2 Multiple Choice Worth 5 points)
Answer:
football
Explanation:
I took the 2.10 quiz and got it wrong so it must be football
An average family of four uses roughly 1200 Liters of water per day (1L. - 1000 cm3). A lake that covers 50 km² with a uniform depth and
supplies water to a local town with a population of 40,000 people would lose depth every year due to water consumption form
the locals, Ignore evaporation, rain, creeks and rivers.
Answer:
#_total = 4.38 10⁹ liter
Explanation:
For this exercise we can use a direct proportion rule (rule of three). If 4 people use 1200 liters how much water 1 person consumes
#_water = 1 person (1200 liter / 4 person)
#water = 300 liters
Now we look for the consumption of this person in a year, if 1 person consumes 300 liters 1 day, how many liters they consume in a year (365 days)
#_water_person_total = 365 days (300 liters / 1 day)
#_water_person_total = 109500 liters
This is the water consumption of 1 person in a year, the total of 40000 people how much they consume
#_total = 40000 person (109500 liter / 1 person)
#_total = 4.38 10⁹ liter
