Answer:
C. gasses pushing a rocket forward
Explanation:
How can one find the mechanical advantage of a pulley?
Answer:
To calculate the mechanical advantage of a pulley you simply have to count the number of rope sections that support whatever object you are lifting (not counting the rope that is attached to the effort)
Example:
For example, in a one pulley system the MA is 1. In a two pulley system the MA is 2. The more compound the pulley is the easier the load is to lift. If you were lifting a 600kg object with 2 pulleys you would have to use enough effort to pull 300kg to lift the 600kg object! Therefore your mechanical advantage would be 2 (600/300).
MA= load/effort OR number of rope sections
Please help
Right answers please
Will mark brainliest
Answer:
a. 45 N. / b. 0.08 m/s^2. / c. 102 N
F = ma
F = 15(3)
F = 45 newtons
F/m = a
20/250 = a
0.08 m/s^2 = a
R = ma
R =1.5(68)
102 N
I beggggg youu to solve this for me, I'm giving you 60 POINTS !!!
please solve it on a paper and send it i should submit it tomorrow it's graded
Answer:
but where is the question ?
Explanation:
hope it works out
Answer:
where the question about?
Explanation:
I think the question is invisible
what happens to the moleclues within a gas when the gas Condeenses
What is the symbol for Pressure ? Help
Answer:
The answer is Pascal or Pa.
Answer:
Pa or small p
Explanation:
Force over Area. The SI unit is Pascal
what is the defination of temperature
Answer:
Temperature is a physical property of matter that quantitatively expresses hot and cold
Explanation:
Answer:
Temperature is the degree of hotness or coldness in a body
Explanation:
it is measured by the Average kinetic energy of the body. It is independent of the mass,it's measured in °C(Celsius),K(kelvin),°F(Fahrenheit)
A wave has an amplitude of 2 cm. What is its energy (KW)?
Answer:
1.962 × 10⁻³ kW
Explanation:
The energy of a wave of a wave, such as an ocean wave, in regions of considerable water depth given its amplitude in a meter of crest and surface unit is given by the relation;
[tex]E = \dfrac{\rho \times g \times A^2}{2}[/tex]
Where:
ρ = Density of water = 1000 kg/m³
g = Acceleration due to gravity = 9.81 m/s²
A = Wave amplitude = 2 cm = 0.02 m
We therefore have;
[tex]E = \dfrac{1000 \times 9.81 \times (0.02)^2}{2} = 1.962 \ \dfrac{m^2 \cdot kg}{s^2} = 1.962 \ J[/tex]
The energy is power is the energy per second which is gives;
P = E /second = 1.962 J/s = 1.962 W = 1.962 × 10⁻³ kW.
A 0.50 kilogram ball is held at a height of 20 meters. What is the kinetic energy of the ball when it reaches halfway after being released?
A.
49 joules
B.
98 joules
C.
1.0 × 102 joules
D.
1.1 × 102 joules
Answer:
A
Explanation:
Use the conservation of energy formula to calculate the velocity of the ball when it reaches the halfway point (10m down). Then, use your calculated value to obtain the kinetic energy.
Answer:
A. 49 on Plato
Explanation:
Its the right one trust me .
Density changes are responsible for which method of thermal energy transfer.
Answer:
convection
Explanation:
because in convection, molecules move with heat(i.e wind). So, when molecules move to another place, the mass will be reduce and the density will change
plzz help! i need it now!!!!
be 100% sure of the answer plzzz
Answer:
Equal effort force
Explanation:
A class 1 lever has the support between the load and the effort hence the load tilts the plain at one end containing the support we would require an effort equal and opposite to the load to ensure movement .
In which space, outdoors or in your classroom, would it be easier to hear a musician? Explain
Answer:
It is easier to hear a musician in the classroom than outdoors
Explanation:
It is easier to hear a musician in the classroom due to the improved acoustics provided by the walls of the classroom whereby along with the direct sound of the musician, which is the lead source of the sounds, there is an increased number of indirect sound reaching the ear in the classroom than outdoors and due to precedence effect, all the sound appear to come from the musician
In music played outside, along side the direct sound from the musician, the indirect sound that reach the ear is echoed from maybe by only the ground while the majority of the sound from the music wanders away with the wind and in other directions as well as being absorbed such that speakers will be required to improve the sound of the music outdoors.
what is the wavelength of the radio waves transmitted by an FM station at 90MHz where 1M=10^6 AND THE SPEED OF RADIOWAVE IS 3*10^8m/s
Answer: 0.3m
Explanation:
Given the following :
Speed of radio wave(V) = 3 × 10^8 m/s
If 1M = 10^6
Frequency(F) = 90MHz = 90 × 10^6
Wavelength (λ) =?
Speed of wave (V) = frequency(F) × wavelength(λ)
V = fλ
(3 × 10^8) = (90 × 10^6) × λ
λ = (90 × 10^6) / (3 × 10^8)
λ = 30 × 10^(6 - 8)
λ = 30 × 10^-2
λ = 0.3m
Define the term displacement. Is it a vector quantity or a scalar quantity?
Explanation:
The difference between final and initial position of an object is called its displacement. Its formula is given by :
[tex]\text{displacement}=\text{final position}-\text{initial position}[/tex]
It is equal to the shortest path covered by it. It is a vector quantity. It has both magnitude and direction.
How much power is used by 4 A appliance that is plugged into a 120 V circuit for 4 minutes
Answer:
Power, P = 480 W
Explanation:
It is required to find the power used by 4 A appliance that is plugged into a 120 V circuit for 4 minutes. Power used by an appliance is given by the formula as follows :
[tex]P=VI[/tex]
Plugging all the values we get :
[tex]P=120\times 4\\\\P=480\ W[/tex]
So, the power used by the appliance is 480 W.
Ed biked home from school in 400 seconds. His home is located 2000 m south of the school. What was his velocity?
[tex]answer = 5 \: \: metre \: per \: second\\ distance = 2000 \: m \\ time = 400 \: seconds \\ velocity = \: \frac{distance \:t ravelled}{time \: taken} \\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: = \frac{2000}{400} \\ \: \: \: \: \: \: \: \: \: = 5 \: metre \: per \: second \\ hope \: it \: helps[/tex]
When salt is added to the water what happens to the surface?
Answer:
it increases the surface tension of the water
The diagram below shows a 5.0-kilogram bucket of water being swung in a horizontal circle of 0.70-meter radius
at a constant speed of 2.0 meters per second.
5.0-kg Bucket
0.70 m
The magnitude of the centripetal force on the bucket of water is approximately
1) 5.7 N
2) 14 N
3) 29 N
4) 200 N
Answer:
F = 29 N
Explanation:
We have,
Mass of the bucket of water is 5 kg
Radius of a horizontal circle is 0.7 m
Speed of the circle is 2 m/s
It is required to find the magnitude of centripetal force on the bucket of water. The formula used to find the magnitude of centripetal force is given by :
[tex]F=\dfrac{mv^2}{r}\\\\F=\dfrac{5\times (2)^2}{0.7}\\\\F=28.57\ N[/tex]
or
F = 29 N
So, the centripetal force on the bucket of water is 29 N.
The magnitude of the centripetal force on the bucket of water is approximately 29 N
Definition of centripetal forceCentripetal force is the force that acts to keep an object moving in a circular motion. It is expressed mathematically as:
F = mv² / r
With the above formula, we can obtain the centripetal force acting on the bucket.
How to determine centripetal force•Mass (m) = 5 Kg
•Radius (R) = 0.7 m
•Velocity (v) = 2 m/s
•Centripetal force (F) =?
F = mv² / r
F = (5 × 2²) / 0.7
F = (5 × 4) / 0.7
F = 20 / 0.7
F = 29 N
Learn more about centripetal force:
https://brainly.com/question/10596517
conditions for equilibriam
Jess wants to make her house more energy efficient. She has two options, A or B. Option A is double-glazing her patio doors, which will cost £350 and save £15 per year. Option B is insulating her loft, which will cost £460 and save £25 per year. Is option A or option B the better long-term option?
Jess wants to make her house more energy efficient. Insulating her loft, which will cost £460 and save £25 per year, is better long-term option. Therefore, option B is correct.
What is energy ?In order to accomplish work and to produce heat and light, energy must be transferred to a body or to a physical system. Energy is the quantitative attribute that does this. Energy is a preserved resource; according to the rule of conservation of energy, energy can only be transformed from one form to another and cannot be created or destroyed.
Computers, vehicles, communications, state-of-the-art medical technology, and many other things are all powered by energy. The demand for dependable and economical energy is especially pressing for emerging countries. It may enhance things or perhaps save lives.
A turbine generator set transforms mechanical energy into electrical energy to produce electricity. Natural gas, coal, nuclear fission, biomass, petroleum, geothermal, and solar thermal are examples of energy sources where the heat generated is used to produce steam.
Thus, option B is correct.
To learn more about energy, follow the link;
https://brainly.com/question/1932868
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why does a balloon filled with hydrogen rises up only to a certain height
Answer: they will rise up because hydrogen is lighter in density and it's weight is lower when it's in the air
Explanation:
Answer:
hydrogen is less dense and its weight is also less than the air.
Explanation:
If kinetic energy of a body is increased by 125%, the percentage increase in Momentum is?
Answer:
50 %
Explanation:
It's Fifty percent
If a guitar string vibrates at 304hz as its fundamental frequency, what is the frequency of the third harmonic?
Answer:
912 Hz
Explanation:
Third harmonic multiplies the frequency by 3. Harmonics are waves that operate at a frequency that is an integer (whole-number) multiple of the fundamental frequency.
Please answer these: Q1. i. In what two ways combustion can be useful to us? Explain by giving examples. ii. Explain why decomposition of sugar on heating is an irreversible change. Q2. In order to answer this question you need to look around your immediate surroundings to find examples of rusting of iron or any other metal. i. What makes iron rust? ii. Why is the rusting of iron a problem? Give any 3 examples from daily life where rusting has been a disadvantage. iii. Suggest any two ways that can help prevent rusting of iron. Q3. i. Give two differences between a physical change and a chemical change. ii. Explain whether condensation of water vapour is a physical or a chemical change. iii. Write word equations for the following reactions: a. Breaking down/ electrolysis of water b. synthesis of water c. decomposition of sugar d. photosynthesis in plants
Answer:
1) combustion can be used as a source of energy.
Combustion is used to power rockets
ii) Decomposition of sugar is a chemical change and new substances are formed.
2)corrosion of pipes
Corrosion of bridges
Corrosion of knives and blades at home
I) iron rusts due to the action of air and moisture bon the metal setting up an electrochemical process in which the iron is the anode. This leads to the corrosion of the iron metal.
ii) Rusting is a problem because it reduces the economic value of iron. Rust weakens iron and threatens the integrity of materials made from iron.
Iron rusting may lead to the collapse of a bridge
Iron rusting makes a blade blunt
Iron rusting weakens pipes made of iron
iii) Rusting of iron can be prevented by galvanizing the iron or by painting the iron.
3) chemical change leads to the formation of a new substance while physical change does not lead to the formation of a new substance.
Chemical changes are not easily reversible while physical changes are easily reversible.
ii)condensation of water vapour is a physical change
iii)
Electrolysis of water;
Two moles of water---> two moles of hydrogen gas + one mole of oxygen gas
Synthesis of water;
two moles of hydrogen gas + one mole of oxygen gas---->Two moles of water
Decomposition of sugar;
One mole of Sucrose---> twelve moles of carbon + eleven moles of water + heat
Six moles of carbon dioxide + six moles of water +energy------> one mole of sugar + six moles of oxygen
Explanation:
Combustion is useful as a source of energy because it is used in power generation. Currently, combustion is being used to power rockets. It is also used as a way of providing heat at home.
One of the characteristics of a chemical change is that it leads to the formation of new substances. Since the decomposition of sugar leads to the formation of carbon and water, it is an irreversible chemical change.
When water is heated, it is converted into vapour which can settle on a surface and convert back to liquid water. This is a physical change.
A 1.2 m steel rod moves through a uniform magnetic field of 0.020 T at 30 m/s. What emfis induced between the two ends of the steel rod?
0.36 V
0.50 V
0.60 V
0.72 V
Answer:
0.50v
Explanation:
Now EMF is induced when there is motion of a conductor in an electric field. Michael Faraday in the annals of scientific history discovered this.
This is expressed mathematically as;
E = Magnetic field / t
but t = d/ v; d- distance, v-velocity, time
Hence E = magnetic field/ d/v
= Magnetic field× v/ d
= 0.02×30/ 1.2= 0.5
A curium-242 (Z= 96) can be produced by positive-ion bombardment when an alpha particle collides with which of the following nuclei? Note: A neutron is also a product of this bombardment, in addition to the curium-242.
A. Pu -239
B. U -239
C. Am-241
D. Cf-249
E. Pu-241
Answer:
A. Pu -239
Explanation:
An isotope is an element with the same atomic number but different mass number. most isotope are unstable, having short half life.
Curium-242 is an isotope produced when Plutonium 239 is bombarded by an alpha particle. This reaction between Plutonium 239 and alpha particle gives curium-242, neutron and a high amount of energy as the products.
Curium oxidizes easily, and it is a dangerous metal which can cause cancer initiation when absorbed by biological materials e.g bones or tissue.
Consider a cylindrical crew module with a diameter of 5 meters, a length of 15 meters, and a crew of 6 people. The module contains air that is at
standard sea-level atmospheric pressure and temperature. The sea level density of air at 20 degrees Celsius is 1.204 kg/m3.
What is the volume of the crew module? Provide your answer in m' with at least 2 decimal places.
Answer:
294.524 m^3
Explanation:
The volume of a cylinder is given by the formula ...
V = πr^2h
For a radius of 2.5 m and a length of 15 m, the volume is ...
V = π(2.5 m)^2(15 m) = 93.75π m^3 ≈ 294.524 m^3
The volume is about 294.52 cubic meters.
Please explain how you got the answer :(
Answer:
36.5 kJ
Explanation:
Energy by machine = energy to machine × efficiency
E = 52.1 kJ × 0.70
E = 36.5 kJ
For a moving object, the force acting on the object varies directly with the objects acceleration. When a force of 24N acts on a certain object, the acceleration of the object is 3m/s^2. If the acceleration of the object becomes 10m/s^2, what is the force
Answer:
80 N
Explanation:
From the question,
F = ma .......................... Equation 1
Where F = Force, m = mass of the object, a = acceleration of the object.
make m the subject of the equation
m = F/a.................... Equation 2
Given: F = 24 N, a = 3 m/s²
Substitute into equation 2
m = 24/3
m = 8 kg.
If the acceleration of the object becomes 10 m/s²,
Substitute into equation 1
F = 10(8)
F = 80 N.
Two forces oppose each other while a star is stable. The first is gravity pulling inward. What is the
other force?
Answer:
the radiation pressure that has to push the star
Explanation:
In the stars there are two forces that act in the opposite direction.
- On the one hand there is the force of gravity that the star has to collapse
- On the other is the radiation pressure that has to push the star. This pressure comes from the radiation and velocity of the particles involved in nuclear reactions.
what are two things that are infinite?
Answer:
Infinity = Never ending
Explanation:
The universe could be infinite, both in terms of space and time, but there is currently no way to test whether it goes on forever or is just very big. The part of the universe we are able to observe is finite, measuring about 46 billion light years in diameter.
The set of natural numbers is an infinite set. This kind of infinity is, by definition, called countable infinity. All sets that can be put into a bijective relation to the natural numbers are said to have this kind of infinity. This is also expressed by saying that the cardinal number of the set is aleph-naught (ℵ0).
Hope this helps. Mark as brainliest!
STARS ARE INFINITE , NUMBERS ARE INFINITE
Explanation:
