Den pushes a desk 400 cm across the floor. He exerts a force of 10 N for 8 s to move the desk. What is his power output? (Power: P = W/t) 1.25 W 5 W 40 W 500 W

Answer:

Final velocity = 119.83 m/s

Final elevation = 731.9 m

Explanation:

We are told that temperature of air changes from 0 to 10°C

Thus;

Change in temperature; ΔT = 10 - 0 = 10°C

Also, its velocity changes from zero to a final velocity. Thus;

v1 = 0 m/s

v2 is unknown

Also, its elevation changes from zero to a final elevation.

So, z1 = 0 and z2 is unknown

Now, we want to find v2 and z2 when the internal, kinetic and potential energy are equal.

Thus Equating the formula for both kinetic and internal energy gives;

½m(v2² - v1²) = mc_v•ΔT

m will cancel out and v1 is zero to give;

v2² = 2c_v•ΔT

v2 = √(2c_v•ΔT)

Where c_v is specific heat of constant volume of air with a constant value of 718 J/Kg.K

Thus;

v2 = √(2 × 718 × 10)

v2 = √14360

v2 = 119.83 m/s

To find z2, we will equate potential energy formula to that of the internal energy.

Thus;

mg(z2 - z1) = mc_v•ΔT

m will cancel out and since z1 is zero, then we have;

z2 = (c_v•ΔT)/g

z2 = 718 × 10/9.81

z2 = 731.9 m

It isn't best to wear loose fitting clothing when exercising, as you may not feel too comfortable. It depends on the person. However there are a few advantages.

• Tight clothing may not be comfortable as well

• Looser clothing allows easy evaporation of sweat

Then again when it says " loose - fitting " it may mean not too baggy. Baggy clothing can have an impact on your physical activity.

Answer All of the above

For people on a p e x

Answer:

The longer the wave, the deeper the wave base - True

The greater the wave height, the deeper the wave base - false

The longer the wave, the faster the wave travels- true

The greater the wave height, the faster the wave travels- false

The faster the wave, the greater the wave height - False

Explanation:

When a wave has a high length it means that the wave base will be deeper.

The longer the wave, the deeper the wave base - True

When the weight height is big , the wave base will be deeper.

The greater the wave height, the deeper the wave base - false

The longer the wave, the faster the wave travels- true

The greater the wave height, the faster the wave travels- false

The faster the wave, the greater the wave height - False

Answer:

its velocity, wavelength and frequency all change

Explanation:

Whenever a wave crosses the boundary between two media of different densities, its velocity, frequency and wavelength changes. This appears as a bending of the wave as it crosses the boundary from one medium to another.

Refraction is a fundamental property of waves. Hence when light is travelling from air into water, it wavelength, speed and frequency all changes at the interface between the two media.

Answer:

C. sound energy

Explanation:

hope this helps

Answer:

proton and neutron respectively.

Explanation:

Atoms of the same element will always have the same number of proton but will have different numbers of neutron if their mass numbers are different.

Answer:

8 atm

Explanation:

Ideal gas law:

PV = nRT

where P is pressure, V is volume, n is moles, R is universal gas constant, and T is absolute temperature.

If n is constant:

PV / T = PV / T

(4 atm) (60 L) / (27 + 273) K = P (40 L) / (127 + 273) K

0.8 atm = 0.1 P

P = 8 atm

Answer:

Reason:- We use cotton to make the wick of a spirit lamp because cotton has thread strands which act like fine capillaries and help in drawing up a steady supply of oil in the lamp for burning by capillary action

Explanation:

Answer:

0.699 L of the fluid will overflow

Explanation:

We know that the change in volume ΔV = V₀β(T₂ - T₁) where V₀ = volume of radiator = 21.1 L, β = coefficient of volume expansion of fluid = 400 × 10⁻⁶/°C

and T₁ = initial temperature of radiator = 12.2°C and T₂ = final temperature of radiator = 95.0°C

Substituting these values into the equation, we have

ΔV = V₀β(T₂ - T₁)

= 21.1 L × 400 × 10⁻⁶/°C × (95.0°C - 12.2°C)

= 21.1 L × 400 × 10⁻⁶/°C × 82.8°C = 698832 × 10⁻⁶ L

= 0.698832 L

≅ 0.699 L = 0.7 L to the nearest tenth litre

So, 0.699 L of the fluid will overflow

6. Force

7 speed

8 distance

9 acceleration

Answer:

Electromagnetic waves or EM waves are waves that are created as a result of vibrations between an electric field and a magnetic field. In other words, EM waves are composed of oscillating magnetic and electric fields.

Explanation:

Answer:

The name of the force is elastic (spring) force

Explanation:

The elastic force which is the restoration force of an elastic (spring like) object that tries to return to its initial non-stretched state built up by the pulling of the bow by the archer (using the muscles) pushes on the arrow which the archer releases the same time he leaves the bow string, and the arrow flies in the direction already pointed by the archer

The arrow ultimately falls down due to gravity forces that acts on all objects within the Earths gravitational field. However due to the speed of constant horizontal speed of the arrow and increasing downward speed of the due to the gravity force, the falling of the arrow looks disappointing.

Explanation:

The asked in the Question is missing, although i am assuming the number

as [tex]\frac{6}{23}[/tex] ÷[tex]\frac{\sqrt{2} }{2}[/tex].

The given expression contains an irrational number. So, the quotient will also be an irrational number.

Solving

[tex]\frac{6}{23}\times\frac{\sqrt{2} }{2} \\=\frac{3\sqrt{2} }{23}[/tex]

Which is an irrational number.

Answer:

True

Explanation:

Thats is true since it cannot be a vector because speed only gives a magnitude, not a direction as well.

Answer:

number 6 is wrong

the answer is pesticides

2.combines are used for harvesting or threshing.so number 2 is wrong

at least you tried

Explanation:

there is no such thing as weedicides

Answer:

1. True

2.True

3.False

4. True

5. True

6.False

7.False

8.True

9.False

10.False

Answer:

1) Tailored software  Library management system

2) Utility software Scan viruses

3) Operating system Used to coordinate the hardware of the computer

4) Packaged software set of programs Microsoft office

Explanation:

1) A tailored software, also known as a custom software, is one that is designed and tailor-made only for a particular organisation

2) A utility software is a computer maintenance and analysis software used to enable proper functioning of the computer by performing restorative and maintenance tasks

3) Operating system software

The operating system software controls the operation of the computer hardware within the system and enables the operation of other programs in the computer

4) Packaged software are a collection of programs that are oriented to perform interrelated tasks that a focused to a particular area, such as Microsoft Office.

Answer:

Sound travels fastest through solids.

Explanation:

This is because molecules in a solid medium are much closer together than those in a liquid or gas, allowing sound waves to travel more quickly through it. In fact, sound waves travel over 17 times faster through steel than through air.

Sound waves move the fastest through the solid. The speed of the sound wave  in the liquid and gas is low,

A sound wave is produced when a medium begins to vibrate. When an entity vibrates, a pressure wave is formed, which causes sound.

Solids transmit sound the fastest. Because the molecules in a solid medium are much closer together than in a liquid or gas, sound waves can move through it much faster.

Hence, sound waves move the fastest through the solid.

To learn more about the sound wave, refer to the link;

https://brainly.com/question/11797560

#SPJ2

Answer:

Infrasound vs. Ultrasound: Infrasound is sound that is below the lower limit of human hearing, below 20 Hz, and ultrasound is above the upper limit of human hearing, above 20,000 Hz.  Individuals use infrasound - this recurrence run for checking seismic tremors and volcanoes, graphing rock and oil developments underneath the earth. Infrasound is described by a capacity to get around hindrances with little scattering.  

For instance, a few creatures, for example, whales, elephants and giraffes convey utilizing infrasound over significant distances. Torrential slides, volcanoes, seismic tremors, sea waves, water falls and meteors produce infrasonic waves. Symptomatic ultrasound, additionally called sonography or demonstrative clinical sonography, is an imaging technique that utilizes high-recurrence sound waves to create pictures of structures inside your body. The pictures can give important data to diagnosing and treating an assortment of ailments and conditions.

Explanation:

idk how many words this is but its a start for u to add on to and i hope this helps and its in my own words - pls mark me brainiest

Answer:

Explanation:

a) From the diagram, the load will be expressed in newton. The load will be the weight of the box on the inclined plane.

Load = mass * acceleration due to gravity.

Given the mass of the object = 100kg

acceleration due to gravity = 9.8m/s²

Load (in Newton) = 100*9.8

Load (in Newton) = 980N

b) The formula for calculating the velocity ratio of an inclined plane is expressed as VR = 1/sinθ where θ is the angle of inclination.

Given θ = 30°,

VR = 1/sin30°

VR = 1/0.5

VR = 1/(1/2)

VR = 1* 2/1

VR = 2

The velocity ratio is 2.

c) Length of the inclined plane can be calculated using the SOH, CAH, TOA trigonometry identity.

According to SOH, sinθ = opposite/hypotenuse

sin30°  = 1/2 = opp/hyp

This shows that the opposite side of the triangle is 1 and the hypotenuse is 2. The length if the inclined is the length of the longest side i.e the hypotenuse. Hence the length of the inclined plane is 2m

d) Mechanical Advantage is the ratio of the load to the effort applied on an object.

Given the Load = 980N and the effort applied to the load on the incline plane = 400N

MA = Load/Effort

MA = 980/400

MA = 2.45

e) Efficiency = MA/VR * 100

Efficiency = 2.45/2 * 100

Efficiency  = 122.5%

Answer:

20 N

Explanation:

In air, the normal force is equal to the weight.

∑F = ma

N − mg = 0

N = mg

Submerged in water, the normal force is equal to the weight minus the buoyant force:

∑F = ma

B + N − mg = 0

N = mg − B

Plugging in values:

80 N = 100 N − B

B = 20 N

Answer:

Reproducible by other scientists

Explanation:

I just took the test

Answer:

The spring was compressed the following amount:

[tex]\Delta x=\sqrt{ \frac{m_1\,v_1^2+ m_2\,v_2^2}{k} }[/tex]

Explanation:

Use conservation of energy between initial and final state, considering that the surface id frictionless, and there is no loss in thermal energy due to friction. the total initial energy is the potential energy of the compressed spring (by an amount [tex]\Delta x[/tex]), and the total final energy is the addition of the kinetic energies of both masses:

[tex]E_i=\frac{1}{2} k\,(\Delta x)^2\\\\E_f=\frac{1}{2} m_1\,v_1^2+\frac{1}{2} m_2\,v_2^2[/tex]

[tex]E_i=E_f\\[/tex]

[tex]\frac{1}{2} k\,(\Delta x)^2=\frac{1}{2} m_1\,v_1^2+\frac{1}{2} m_2\,v_2^2\\k\,(\Delta x)^2=m_1\,v_1^2+ m_2\,v_2^2\\(\Delta x)^2=\frac{m_1\,v_1^2+ m_2\,v_2^2}{k} \\\Delta x=\sqrt{ \frac{m_1\,v_1^2+ m_2\,v_2^2}{k} }[/tex]

Answer:

First, as you may know, the light travels at a given velocity.

In vaccum, this velocity is c = 3x10^8 m/s.

And we know that:

distance = velocity*time

Now, if some object (like a star ) is really far away, the light that comes from that star may take years to reach the Earth.

This means that the images that the astronomers see today, actually happened years and years ago (So the night sky is like a picture of the "past" of the universe)

Also, for example, if an astronomer sees some particular thing, he can apply a model (a "simplification" of some phenomena that is used to simplify it an explain it) and with the model, the scientist can infer the information of the given thing some time before it was seen.

The astronomers could know what was happening inside galaxies way back then by the fact that;

they examine the spectra of galaxies (or the overall colors of galaxies) with the highest redshifts they can find

Astronomers Measure the wavelength of the light that is stretched, so the light is seen as 'shifted' towards the red part of the spectrum by using spectroscopy. This measure is also called redshift.

This invokes a ray of light through a triangular prism that splits the light into various components known as spectrum.

The way the astronomers could use this concept to know what was happening in the galaxies before is by examining the spectra of galaxies that have the highest redshifts.

Read more at; https://brainly.com/question/15995216

Answer:

The distance Mr Franklin applied the force is 400 m

Explanation:

The efficiency of the machine = 80%

The force applied by the machine = 800 N

The distance over which the force is applied by the machine = 20 m

The force applied by Mr. Franklin = 50 N

The work done by the machine = 800 × 20 = 16000 J

The ideal work at 100% efficiency = X

80% of X = 16000 J

X = 16000 N/0.8 = 20,000 J

Therefore, we have have;

Work = Force × Distance;

20,000 J = 50 N × Distance Mr Franklin applied the force

Distance Mr Franklin applied the force = 20,000 J/(50 N) = 400 m

The distance Mr Franklin applied the force = 400 m.

Answer:

the awnser in 400m

Explanation:

did the test on edge 2020 and got it right

Answer:

V = 26.6 volts

Explanation:

Let Initial Potential Difference be V.

Charge (Q) accumulated in 30 mF Capacitor =

Q = C * V

Q= 30 * V

Now, Common Potential after connecting to uncharged 10mF capacitor in parallel = 20 Volt

Total Charge =Total Capacity * Common Potential

30 * V = ( 30 + 10) * 20

V = 26.6 volts

The unknown potential across the 30-µF capacitor is 6.67 V.

The given parameters;

Since the potential difference between the two capacitors are different, the two capacitors are in series connection.

In series circuit arrangement, the quantity of charge flowing in each capacitor is the same.

[tex]Q_{30\ \mu F} = Q_{10 \ \mu F}[/tex]

[tex]Q_{10 \ \mu F} = CV = 10\times 10^{-6} \times 20 = 0.0002 \ C[/tex]

The potential difference are different and the total potential is given as;

[tex]V_{T} = V_1 + V_2\\\\V_1 = \frac{Q}{C_1} \\\\V_2 = \frac{Q}{C_2} \\\\V_1+V_2 = \frac{Q}{C_1} + \frac{Q}{C_2}\\\\V_1 + V_2 = Q(\frac{1}{C_1} + \frac{1}{C_2} )\\\\V_1 + 20 = Q(\frac{1}{C_1} + \frac{1}{C_2} )\\\\V_1+ 20 = \frac{Q(C_2+ C_1)}{C_1 C_2} \\\\V_1 = \frac{Q(C_2+ C_1)}{C_1 C_2} - 20[/tex]

[tex]V_1 = \frac{0.0002(10\times 10^{-6}\ + \ 30\times 10^{-6})}{(30\times 10^{-6}) (10\times 10^{-6})} - 20\\\\V_1 = \frac{8\times 10^{-9}}{3\times 10^{-10}} - 20\\\\V_1 = 26.67 - 20\\\\V_1 = 6.67 \ V[/tex]

Thus, the unknown potential across the 30-µF capacitor is 6.67 V.

Learn more here:https://brainly.com/question/23899758

Answer:

1.  to relate the type of box material to the temperature of the air within the box

2. Question is incomplete

3. scatterplot

Explanation:

1. The only thing done differently in this experiment is the type of material used in making the boxes, hence the experiment must be about that. Before proceeding to answering this question, we must have this at the back of our minds.

We can gather from the experiment that the boxes are of the same size and were subjected to sunlight for an hour (the same time duration for both). Hence, the temperature of the air inside the box will only be affected by the type of material the box is made of since the boxes have the same size and were subjected to sunlight for the same duration.

From the options provided, the best description for this experiment is; to relate the type of box material to the temperature of the air within the box.

2. The question is incomplete. The value for speed/velocity needed to calculate the average time is missing.

However, the formula needed here is velocity = distance ÷ time

3. There are two variables in this experiment; distance and time

The type of graph that shows two variables on it (of the options provided) is the scatterplot.

Answer:

Its inductance L = 166 mH

Explanation:

Since a current, I = 0.698 A is obtained when a voltage , V = 5.62 V is applied, the resistance of the coil is gotten from V = IR

R = V/I = 5.62/0.698 = 8.052 Ω

Since we have a current of I' = 0.36 A (rms) when a voltage of V' = 35.1 V (rms) is applied, the impedance Z of the coil is gotten from

V₀' = I₀'Z where V₀ = maximum voltage = √2V' and I₀ = maximum current = √2I'

Z = V'/I' = √2 × 35.1 V/√2 × 0.36 V = 97.5 Ω

WE now find the reactance X of the coil from

Z² = X² + R²

X = √(Z² - R²)

= √(97.5² - 8.05²)

= √(9506.25 - 64.8025)

= √9441.4475

= 97.17 Ω

Now, the reactance X = 2πfL where f = frequency of generator = 93.1 Hz and L = inductance of coil.

L = X/2πf

= 97.17/2π(93.1 Hz)

= 97.17 Ω/584.965 rad/s

= 0.166 H

= 166 mH

Its inductance L = 166 mH

Answer:

Inversely proportional

Explanation:

P.E ∞ h

K.E ∞ v

v ∞ 1/h

Therefore

K.E ∞ 1/h

Then

P.E ∞ 1/(K.E)

Answer:

Inversely

Explanation:

Explanation:

The answer is option B

The number of reactant molecules and product molecules is even.

Answer:

The angular frequency of the block is ω = 5.64 rad/s

Explanation:

The speed of the block v = rω where r = amplitude of the oscillation and ω = angular frequency of the oscillation.

Now ω = v/r since v = speed of the block = 62 cm/s and r = the amplitude of the oscillation = 11 cm.

The angular frequency of the oscillation ω is

ω = v/r

ω = 62 cm/s ÷ 11 cm

ω = 5.64 rad/s

So, the angular frequency of the block is ω = 5.64 rad/s