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3 years ago

Work can _____ energy between objects and can cause a change in the form of energy.

Physics

1 answer:

zhuklara [117]3 years ago

6 0

Answer:

Work can transfer energy between objects and can cause a change in the form of energy.

Explanation:

The best explanation can be done with an example.Consider an apple of mass m falling from a tree. Initially, the apple is at rest on the tree, at a certain height h above the ground, so it has a form of energy called gravitational potential energy, equal to: where g is the acceleration due to gravity.As the apple falls, the force of gravity acts on it, and so this force does work on the apple. As a result, the potential energy of the apple is converted into another form of energy, kinetic energy, which is the energy due to the motion of the apple: where v is the speed of the apple.Consider another example: a man pushing a box along the floor with a force F. The man is doing work on the box, and this work is equal towhere d is the displacement of the box. As a result of this work, some of the chemical energy contained in the muscles of the man is transferred into the box and converted to kinetic energy of the box, which is put in motion and it gains a certain speed v. In particular, if there are no frictional forces involved, the work done by the man is equal to the kinetic energy gained by the box.

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A grating has 470 lines/mm. how many orders of the visible wavelength 538 nm can it produce in addition to the m = 0 order?

Natali [406]

Three complete orders on each side of the m=0 order can be produced in addition to the m=0 order.

The ruling separation is d=1/(470mm-1)

$= 2.1 \times 10 {}^{ - 3}mm$

Diffraction lines occurs at an angle θ such that dsin=mλ,when λ is the wavelength and m is an integer.

Notice that for a given order,the line associated with a long wavelength is produced at a greater angle than the line associated with shorter wavelength.

we take λ to be the longest wavelength in the visible spectrum (538nm) and find the greatest integer value of m such that θ is less than 90°.

That is,find the greater integer value of m for which mλ<d.

since,d/λ

$= 538 \times 10 {}^{ - 9} m/2.1 \times 10 {}^{ - 6}$

There are three complete orders on each side of the m=0 order.

The second and third orders overlap.

learn more about diffraction from here: brainly.com/question/28168352

#SPJ4

4 0

2 years ago

A 1000 kg car moving at 108 km/h jams on its brakes and comes to a stop. How much work was done by friction?

Nostrana [21]

Answer:

The work done by friction was $-4.5\times10^{5}\ J$

Explanation:

Given that,

Mass of car = 1000 kg

Initial speed of car =108 km/h =30 m/s

When the car is stop by brakes.

Then, final speed of car will be zero.

We need to calculate the work done by friction

Using formula of work done

$W=\Delta KE$

$W=K.E_{f}-K.E_{i}$

$W=\dfrac{1}{2}mv_{f}^2-\dfrac{1}{2}mv_{f}^2$

Put the value of m and v

$W=0-\dfrac{1}{2}\times1000\times(30)^2$

$W=-450000
\ J$

$W=-4.5\times10^{5}\ J$

Hence, The work done by friction was $-4.5\times10^{5}\ J$

3 0

3 years ago

If there are 50 people per square kilometer in a city, and the area of the city is 1.5 × 10 square kilometers. What is the total

qaws [65]

Answer:

750 people

Explanation:

From the question,

Number of people in the city = population density×Area of the city

N = D×A.......................... Equagtion 1

Where N = Number of people in the city, D = population density, A = Area of the city.

Given: D = 50 people per square kilometer, A = 1.5×10 square kilometer.

Substitute into equation 1

N = 50(1.5×10)

N = 750 people.

Hence the total number of people in the city is 750 people.

6 0

3 years ago

If the window is 11 m above the ground, find the time the stone is in flight.

rjkz [21]

d=vi*t+(1/2)gt²

d=11 m
g=9.8 m/s²
vi=0 m/s

11 m=0 m/s*t+(1/2)9.8 m/s²t²
11 m=4.9 m/s²t²
t²=11 m / 4.9 m/s²
t=√(11 m / 4.9 m/s²)=1.489... s≈1.5 s

Answer: the time the sone is in flight is 1.5 s

5 0

3 years ago

Which of the following best describes the circuit shown below?

Rudiy27

Answer:

Short circuit

Explanation:

The given figure shows a short circuit. It is defined as the circuit which allows the flow of electric current when there is no resistance. It shows a battery, bulb and connecting wires.

The wire across the bulb is connected from one terminal to another without any resistance in between them.

So, the correct option is (d) " short circuit ".

3 0

3 years ago

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