Define power and describe how to determine power.

Answers

Answer 1

Answer:Power is a measure of the amount of work that can be done in a given amount of time. Power equals work (J) divided by time (s). The SI unit for power is the watt (W), which equals 1 joule of work per second (J/s). Power may be measured in a unit called the horsepower

Explanation:

Answer 2

Answer:

Explanation:Power equals work (J) divided by time (s).


Related Questions

If an object is accelerating at a rate of 8 m/s^2 what is the mass of the box.

See attached

If an object is accelerating at a rate of 8 m/s^2 what is the mass of the box. See attached

Answers

Answer:

50 kg

Explanation:

fnet=ma

600-200=m8

divide both side by 8 to make m the subject of the formula Thus m=50kg

Convert 360 s to ms? Pls need help

Answers

Answer:

360000

Explanation:

Answer:

360000 milliseconds

Explanation:

I have this remembered dont worry homie i got chu

A milliammeter whose resistance is 120 ohm has full scale deflection with a current of 5mA. How will you use it to measure a maximum current of 100 A​

Answers

Answer:

If 99.995 A  pass thru a shunt and 5 mA pass thru the meter, the meter will have full scale deflection for a current of 100 A.

By Ohm's Law  

99.995 Rs = .005 Rm

Rs = .005 / 99.995 * 120

Rs = .006 ohms

Using a shunt resistance of .006 Ω will produce the required result.

The value of the shunt resistor should be very low to divert most of the current, use a shunt resistor with a value of 0.0012 ohms.

The value of the shunt resistor (Rs) is:

Rs = (Rm × Im) ÷ (If - Im)

where:

Rs = Shunt resistor value

Rm = Resistance of the milliammeter

Im = Full-scale current of the milliammeter

If = Maximum current we want to measure

The shunt resistor value:

Rs = (120 × 5 ) ÷ (100  - 5)

Rs = (0.12 ) ÷ (100 - 0.005)

Rs = 0.12 ÷ 99.995

Rs = 0.00120018 ohms

Since the value of the shunt resistor should be very low to divert most of the current, use a shunt resistor with a value of  0.0012 ohms.

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find the moment of inertia of a point mass 0.005g at aperpendicular distance of 3m from its axis of rotation.​

Answers

Answer:

the moment of inertia is 4.5 × 10⁻⁵ kg.m²  

Explanation:

Given that;

point mass m = 0.005 g = ( 0.005 / 1000 ) = 5 × 10⁻⁶ kg

perpendicular distance r = 3m

We know that a point mass doesn't have a moment of inertia around its own axis but, but using the parallel axis theorem, a moment of inertia around a distant axis of rotation can be determined using;

\(I_{}\) = mr²

so we substitute

\(I_{}\) = (5 × 10⁻⁶ kg) × (3 m)²

\(I_{}\) = (5 × 10⁻⁶ kg) × 9 m²

\(I_{}\)  = 4.5 × 10⁻⁵ kg.m²  

Therefore; the moment of inertia is 4.5 × 10⁻⁵ kg.m²  

     

The moment of inertia of given point mass is 4.5 × 10⁻⁵ kgm² at a perpendicular distance of 3 m.

The moment of inertia of given point mass can be determined by,

\(I = mr^2\)

Where,

\(I\)- moment of inertia

\(m\)- mass = 0.005 g = ( 0.005 / 1000 ) = 5 × 10⁻⁶ kg

\(r\) - perpendicular distance = 3 m

Put the values in the formula,

\(I = (5 \times 10^{-6}{\rm \ kg}) \times (3 {\rm \ m})^2\\\\I = 5 \times 10^{-6}{\rm \ kg} \times 9 {\rm \ m}\\\\I = 4.5 \times 10^{-5} kgm^2\)

Therefore; the moment of inertia of given point mass is 4.5 × 10⁻⁵ kgm².

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What are the magnitude forces at C and D? Please help

What are the magnitude forces at C and D? Please help

Answers

Answer:

D

Explanation:

Beacuse the force got to the bottem first Meaning the andswer is D

The valid digits in a measurement are called the significant digits. True or False

Answers

i think

Answer:

physics. The ______ is a systematic way to observe, experiment, and analyze the world. scientific method. The valid digits in a measurement are called the. significant digits.

Explanation:

truth'

A box with a mass of 0.5 slugs lies on an inclined plane making an angle of 30o with the horizontal. If the coefficient of kinetic friction between the box and the plane is 0.4, what is the magnitude of the force that must be applied parallel to the incline to keep the box moving down the incline at a constant speed

Answers

Answer: 10.98 N

Explanation:

Given

mass of box is \(m=0.5\ slugs\approx 7.3\ kg\)

The coefficient of kinetic friction is \(\mu= 0.4\)

It is given that on the application of force box started moving with constant speed i.e. there is no net external force

\(\Rightarrow F+mg\sin 30^{\circ}=\mu mg\cos 30^{\circ}\\\Rightarrow F=mg(\mu \cos 30^{\circ}-\sin 30^{\circ})\\\Rightarrow F=7.3\times 9.8(0.866\times0 .4-0.5)=-10.98\ N\\\)

The negative sign indicates direction of force is opposite i.e. it must be applied upwards

if the air was solid and we were liquid how would this work

Answers

Answer:

Chaos.

Explanation:

A system is best defined as?

Answers

Answer:

a group of organs working together to perform a function.

Explanation:

a system is best defined as: a group of organs working together to perform a function.

what is the acceleration of the cart at t=8 seconds?
a) 0 m/s^2
b) 10 m/s^2
c) 20 m/s^3
d) -20m/s^2​

what is the acceleration of the cart at t=8 seconds?a) 0 m/s^2b) 10 m/s^2c) 20 m/s^3d) -20m/s^2

Answers

ANSWER:

What is the acceleration of the cart at t=8 seconds?

a) 0 m/s^2b) 10 m/s^2c) 20 m/s^3d) -20m/s^2

Hence the answer us letter a) 0 m/s^2.

That's all I know, Hope it help :)

Use the sentence to answer the question.
A radio telescope detected very short bursts of radio signals that did not seem to fit the pattern of other signals.
What can be inferred from this statement?
(1 point)
A)The radio signals can be detected accurately.
B)The detection of short bursts of radio signals is very common.
C)The radio telescope is unreliable.
D) The observation is a new astronomical phenomenon.

Answers

It can be inferred from this statement that the detection of short bursts of radio waves or fast radio bursts is very common.

Fast or Short radio bursts, are intense, millisecond-long bursts of radio waves with unknown origins.

Since the first FRB was discovered in 2007, hundreds of these brief cosmic flashes have been shown to originate from several, far-off locations throughout the universe.

A significant portion of FRBs emit extremely brilliant radio waves that last only a few milliseconds at most before entirely vanishng, and about 10% of them have been seen to repeat and exhibit patterns.

The source's identity is still unknown due to the isolated character of the observed occurrence. Although a magnetar has been recognised as a potential source, as of 2022, there is no widely acknowledged single explanation.

Given that the bursts barely last a few milliseconds, the sources are assumed to be little larger than a few hundred kilometres.

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Imagine a 15 kg block moving with a velocity of 20 m/s to the left. Calculate the Kinetic Energy of this block. Formula: Work with Units: Variables with units: Final Answer with units:

Answers

Answer:

3000 J (joules)

Explanation:

Use the formula for kinetic energy which is:

\( k.e = \frac{1}{2} mv ^{2} \)

Where m is the mass and v is the velocity. If we put the values into the formula we get: 0.5 * 15 * (20)*(20) = 3000J

What order does energy flow: sun prodecer consumer?

Answers

Energy flows from the Sun to producers, then to primary consumers, secondary consumers, and potentially to tertiary consumers, forming a pyramid-shaped structure that represents the transfer of energy through different trophic levels in an ecosystem.

Energy flows in a specific order through various components of an ecosystem, starting with the Sun and progressing through producers and consumers. This flow of energy is known as the energy pyramid or trophic levels.

At the base of the energy pyramid is the Sun, which is the ultimate source of energy for most ecosystems on Earth. Sunlight provides the energy needed for photosynthesis, a process carried out by plants, algae, and some bacteria, collectively known as producers. These organisms convert solar energy into chemical energy through photosynthesis, using carbon dioxide and water to produce glucose and oxygen. This process captures and stores energy in the form of organic compounds.

The next level in the energy pyramid consists of primary consumers, also known as herbivores. These are animals that feed directly on producers, such as grazing animals or insects that consume plants. Herbivores obtain energy by consuming plant material and breaking down the organic compounds present in the plants into simpler forms, such as sugars and amino acids, through digestion.

Above the primary consumers are the secondary consumers, which are carnivores or omnivores that feed on herbivores. They obtain energy by consuming primary consumers and breaking down the organic compounds in their prey through digestion. This energy transfer continues up the trophic levels, with each level consuming the one below it.

At the top of the energy pyramid are tertiary consumers, which are typically apex predators. They are carnivores that consume other carnivores. Tertiary consumers obtain energy by consuming secondary consumers and breaking down the organic compounds in their prey.

It's important to note that energy is not efficiently transferred between trophic levels. Only a fraction of the energy consumed at each level is converted into biomass and passed on to the next level. This inefficiency is due to processes such as respiration, heat loss, and incomplete digestion.

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A steel ball of mass 0.1kg is moving with a velocity of 4m/s along a frictionless surface of 10N/m. What is the distance through which the spring is comressed?​

Answers

The distance through which the spring is compressed is equal to the kinetic energy of the steel ball divided by the spring constant, i.e. 0.1 kg x 4m/s2/10N/m = 0.04 m.

Computation of Distance moved

Let us begin by Calculating the kinetic energy of the steel ball:

Kinetic Energy = 0.5 x mass x velocity2

Kinetic Energy = 0.5 x 0.1 kg x (4 m/s)2

Kinetic Energy = 0.8 J

Calculate the distance through which the spring is compressed:

Distance = Kinetic Energy/Spring Constant

Distance = 0.8 J/10N/m

Distance = 0.04 m

Compression is the process of reducing the size of a file or data to save disk space and reduce transmission times. Compression is achieved by encoding data using fewer bits than the original representation.

This is done by removing unnecessary or redundant data, such as white space, or by using data compression algorithms. Compression helps make data storage and transmission more efficient.

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(Figure 1) is the potential-energy diagram for a 500 g particle that is released from rest at A . What is the particle's speed at B ?

(Figure 1) is the potential-energy diagram for a 500 g particle that is released from rest at A . What

Answers

Answer:

Explanation:

according to the graph at B the potential energy of the particle is 2J

therefore we can use the kinetic energy equation to calculate the particle's velocity or speed.

\(E_{k} =1/2mv^{2}\)

2J= 1/2*1/2kg*v^2

8=v^2

v= 2√2 ms-1

A wave with a frequency of 17 Hz has a wavelength of 5 meters. At what speed will this wave travel?

Answers

Answer:

85

Explanation:

soln

given that;

frequency=17Hz

wavelength=5m

speed?

formula for wavelength is;

wavelength= speed/frequency

then ; making v the subject formula

we have that v=wavelength*frequency

v=17*5=>85ms

A block of mass 20 kg is being pulled by a force F on a rough horizontal surface. If the
coefficient of friction is 0.4, calculate
a) the normal force, N
b) the static frictional force, f
c) the minimum force required for the block to move with uniform speed​

Answers

The normal force counteracts any vertical force acting on the system and is perpendicular to the surface. So find the weight of the block and add the two forces.

N - W = 0 because we aren’t accelerating in y direction.
W = mg = 20*9.8 = 196 Newtons
N -196 = 0
N = 196

The definition for frictional force is the normal force multiplied by the coefficient. Very simple formula.
N * us = Fs
196*0.4 = 78.4 Newtons

You kind of already found the minimum force. You would need to apply a force larger than 78.4
F - 78.4 = 0 because we are moving at a constant uniform speed
F = 78.4

Total Internal Reflection: A ray of light in glass strikes a water-glass interface at an angle of incidence equal to one-half the critical angle for that interface. The index of refraction for water is 1.33, and for the glass it is 1.43. What angle does the refracted ray in the water make with the normal

Answers

Answer:

θ₄ = 37.2º

Explanation:

For this exercise it must be solved in two parts, the first part we look for the critical angle, for this we use the law of refraction with the angle in the middle of transmission of tea = 90º

        n₁ sin θ₁= n₂ sin  90

        θ₁ = sin⁻¹ \(\frac{n_2}{n_1}\)

        θ₁ = sin⁻¹ (1.33 / 1.43)

        θ₁ = 68.4º

They indicate that the angle of incidence is half of the critical angle

        θ₃ = 68.4 / 2 = 34.2º

Let's use the law of refraction again

         n₁ sin θ₃ = n₂ sin θ₄

         sin θ₄ = \(\frac{n_1}{n_2}\)   sin θ₃

         sin θ₄ = \(\frac{1.43}{1.33}\)  sin 34.2

         θ₄ = sin⁻¹ 0.604345

        θ₄ = 37.2º

A honeybee is in flight between a flower and its hive. Which of the following statements is true?
A) The bee exerts a force on the Earth equal to the force the Earth exerts on the bee.
B)The Earth exerts a greater force on the bee than the bee exerts on Earth.
C) The bee is in flight, but not in orbit, so there is no force of gravity on it.
D) The bee exerts a greater force on the Earth than the Earth exerts on the bee.

Answers

Answer:

D

Explanation:

The statement i.e. true is option d. The bee exerts a greater force on the Earth than the Earth exerts on the bee.

The Flight that lies between the flower and its hive:

When the honeybee is in flight that lies between a flower and its hive.

So here the bee should be exerted a high force on the earth as compared to the earth exerted on the bee.

Therefore, the option d is correct.

And, the rest of the options are wrong.

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65. If Jill was traveling at 300 miles in 4 hours due South what was his velocity in miles per second,
a) 75 miles per hour due south
c) 5 miles per second due south
b) .02 miles per second due south d) 1 mile per hour due south

Answers

Correct answer is A. Divide 300 by 75

The velocity of Jill is 0.02 miles per second due south, the correct option is b.

What is Velocity?

The total displacement covered by any object per unit of time is known as velocity.

the mathematical expression for velocity is given by

\(Velocity = \dfrac{Displacement }{Time }\)

1 hour = 3600 seconds

4 hours = 4*3600 seconds

             = 14400 seconds

Total displacement covered by the Jill = 300 miles

Total time taken by Jill =  14400 seconds

\(Velocity =\dfrac{300 miles }{14400seconds}\)

The velocity of Jill is 0.02 miles per second due south

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How is Newtons second law apply to the egg drop ?

Answers

Answer:

Newton's Second Law is applied because of the acceleration caused by natural forces as the egg is plummeting to the earth. And the amount of acceleration the egg has will be largely affected by the amount of force Mr. Baker uses to hurl the egg to the ground.

Explanation:

hope that helps

d. Two point charges, q1 = +25 nC and q2 = -75 nC, are separated by a distance of 3.0 cm. Find the magnitude and direction of; i. the electric force q1 exerts on q2 [5] ii. the force that q2 exerts on q1 [4] (take k = 9.0 x 109 N.m2 /C2 )

Answers

Answer:

a) F₂₁ = 0.02 N, attracting.

b) F₁₂ = 0.02 N, attracting.

Explanation:

a)

The magnitude of the force that q₁ exerts on q₂ (F₂₁) is given by Coulomb's Law, as follows:

      \(F_{21} = k * \frac{q_{1} *q_{2}}{r_{12}^{2} } = 9e9 N.m2/C2 * \frac{(25e-9C)*(75e-9C)}{(0.03m)^{2}} = 0.02 N (1)\)

Since q₁ and q₂ have opposite signs, the force between them will be always attractive, i.e., from q₂ towards q₁, along the line that joins both charges.

b)

The magnitude of the force on q₁ due to q₂ can be obtained applying Newton's 3rd Law, or using (1), because all parameters are the same, so F₁₂ (in  magnitude) = F₂₁ = 0.02 NAs we have already said, it must be opposite to the one found in a) so it must go from q₁ towards q₂, it is an attracting force also.

Why do covalent and ionic bonds form?

Answers

Answer:

Ionic bonds form when a nonmetal and a metal exchange electrons, while covalent bonds form when electrons are shared between two nonmetals. An ionic bond is a type of chemical bond formed through an electrostatic attraction between two oppositely charged ions.

Explanation:

hope this helps!

A stone is projected at an angle of 60 degree and an initial velocity of 20 ms^(-1). Determine the time of flight:

Answers

Given data:

* The angle of projectile with the horizontal axes is,

\(\theta=60^{\circ}\)

* The initial velocity of the projectile is,

\(u=20ms^{-1}\)

Solution:

The time of flight of the given projectile is,

\(T=\frac{2u\sin (\theta)}{g}\)

where g is the acceleration due to gravity, and T is the time of flight,

Substituting the known values,

\(\begin{gathered} T=\frac{2\times20\times\sin (60^{\circ^{}})}{9.8} \\ T=3.53\text{ s} \end{gathered}\)

Thus, the time of flight for the given projectile is 3.53 seconds.

Electrons and protons travel from the Sun to the Earth at a typical velocity of 3.99 ✕ 105 m/s in the positive x-direction. Thousands of miles from Earth, they interact with Earth's magnetic field of magnitude 2.93 ✕ 10−8 T in the positive z-direction. Find the magnitude and direction of the magnetic force on a proton. Find the magnitude and direction of the magnetic force on an electron.

Electrons and protons travel from the Sun to the Earth at a typical velocity of 3.99 105 m/s in the positive

Answers

The magnitude of the magnetic force on a proton is 1.68 ✕ 10^−16 N, directed towards the negative y-direction. The magnitude of the magnetic force on an electron is also 1.68 ✕ 10^−16 N, but directed towards the positive y-direction.

Begin by using the formula for the magnetic force on a charged particle moving in a magnetic field:

F = q * v * B * sin(θ)

where F is the magnetic force, q is the charge of the particle, v is the velocity of the particle, B is the magnetic field strength, and θ is the angle between the velocity vector and the magnetic field vector.

For a proton, the charge is +e, where e is the elementary charge (1.6 ✕ 10^−19 C). The velocity of the proton is given as 3.99 ✕ 10^5 m/s in the positive x-direction. The magnetic field strength is 2.93 ✕ 10^−8 T in the positive z-direction.

The angle θ between the velocity vector and the magnetic field vector is 90 degrees since the velocity is perpendicular to the magnetic field.

Substituting the values into the formula, we get:

F_proton = (+e) * (3.99 ✕ 10^5 m/s) * (2.93 ✕ 10^−8 T) * sin(90°)

F_proton ≈ 1.68 ✕ 10^−16 N

Since the proton has a positive charge, the magnetic force is directed opposite to the direction of electron flow, which is in the negative y-direction.

Repeat the steps for an electron, but note that the charge is -e. The direction of the force on an electron will be opposite to that of a proton.

F_electron = (-e) * (3.99 ✕ 10^5 m/s) * (2.93 ✕ 10^−8 T) * sin(90°)

F_electron ≈ -1.68 ✕ 10^−16 N

The force on an electron is also 1.68 ✕ 10^−16 N, but directed towards the positive y-direction.

Remember to consider the proper units and take into account the directions of charge, velocity, and magnetic field when calculating the magnetic force on a charged particle.

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a bike is traveling 58 meters in 20 seconds, what is the speed of the bike ​

Answers

The speed of the car traveling 58 meters in 20 seconds is 2.9 m/s.

What is speed?

Speed is the rate of chnage of distance. The S.I unit of speed is meter per seconds (m/s).

To calculate the speed of the car, we use the formula below

Formula:

S = d/t.............................. Equation 1

Where:

S = Speed of the card = Distancet = Time

From the question,

Given:

d = 58 meterst = 20 seconds

Substitute these values into equation 1

S = 58/20S = 2.9 m/s

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Mercury has a mass of
3.30 x 1023 kg, and a radius of
2.44 x 106 m. What is the acceleration
of gravity on its surface?
[?] m/s² Please help!!!

Answers

Answer:

The acceleration due to gravity on the surface of a planet or celestial body is given by the formula:

g = G M / R^2

where G is the gravitational constant, M is the mass of the planet, and R is the radius of the planet.

Plugging in the values for Mercury, we get:

g = (6.674 x 10^-11 m^3/kg s^2) (3.30 x 10^23 kg) / (2.44 x 10^6 m)^2

Simplifying this expression gives:

g = 3.70 m/s^2

Therefore, the acceleration due to gravity on the surface of Mercury is approximately 3.70 m/s^2.

which issue was not a problem that had to be overcome for humans to travel into space
A.High levels of radiation
B.Extreme hot and cold temperatures
C.Lack of government support
D.Lack of oxygen

Answers

Lack of government support is not a problem faced by humans to travel to space.

What is Space travel?

Space exploration or travel refers to employing the use of astronomy and space technology by humans to travel outer space. This is carried out by astronomers using uncrewed robotic space probes and human spaceflight.

Therefore,lack of government support is not a problem faced by humans while traveling to space because it does not require government support and outer space have harsh weather's which are not conducive to humans living on Earth, there is also high level of radiations,emissions of dangerous rays because of it's closeness to sun and also lack of oxygen which can be as a result of non existence of plants that release oxygen during photosynthesis.

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what is fish farming? what are the disease found in its.​

Answers

I know !!!!!!!!!!!!!!!!!!!!!

David tosses an egg horizontally from the top of a building, with an initial velocity of 6.5 m/s. The building is 60m high. The time takes the egg to hit the ground is

Answers

Answer: 3.5 seconds

Explanation:

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