What happens when you increase the number of slits per millimeter (decrease the spacing between slits)?

Answers

Answer 1

Answer:

Increasing the number of slits not only makes the diffraction maximum sharper, but also much more intense. If a 1 mm diameter laser beam strikes a 600 line/mm grating, then it covers 600 slits and the resulting line intensity is 90,000 x that of a double slit. Such a multiple-slit is called a diffraction grating.


Related Questions

Which of the following biotic organisms makes its own energy from inorganic substances?
producers
consumers
decomposers
minerals

Answers

Answer:

producers make its own energy frominorganic substances.

The buoyant force on an object placed in a liquid is (a) always equal to the volume of the liquid displaced. (b) always equal to the weight of the object. (c) always equal to the weight of the liquid displaced. (d) always less than the volume of the liquid displaced.

Answers

Answer:

(c) always equal to the weight of the liquid displaced.

Explanation:

Archimedes principle (also called physical law of buoyancy) states that when an object is completely or partially immersed in a fluid (liquid, e.t.c), it experiences an upthrust (or buoyant force) whose magnitude is equal to the weight of the fluid displaced by that object.

Therefore, from this principle the best option is C - always equal to the weight of the liquid displaced.

To understand the standard formula for a sinusoidal traveling wave.
One formula for a wave with a y displacement (e.g., of a string) traveling in the x direction is
y(x,t)=Asin(kxâÏt).
All the questions in this problem refer to this formula and to the wave it describes.
1) What is the phase Ï(x,t) of the wave?
Express the phase in terms of one or more given variables ( A, k, x, t, and Ï) and any needed constants like Ï
Ï(x,t)=
2) What is the wavelength λ of the wave?
Express the wavelength in terms of one or more given variables ( A, k, x, t, and Ï) and any needed constants like Ï.
λ=
3) What is the period T of this wave?
Express the period in terms of one or more given variables ( A, k, x, t, and Ï) and any needed constants like Ï.
T=
4) What is the speed of propagation v of this wave?
Express the speed of propagation in terms of one or more given variables ( A, k, x, t, and Ï) and any needed constants like Ï.
v=

Answers

Answer:

1) Φ=zero

2)  λ = 2π / k

3)   T = 2π / w

4)  v = w / k

Explanation:

The equation of a traveling wave is

     y = A sin (ka - wt + Ф)

Let's answer using this equation the different questions

1) we see that the equation given in the problem the phase is zero

2) wavelength

       

     k = 2π /λ

      λ = 2π / k

3) The perido

angular velocity is related to frequency

       w = 2π f

frequency and period are related

       f = 1 / T

         

       w = 2 π / T

        T = 2π / w

4) the wave speed is

         v = λ f

          λ = 2π / k

          f = w / 2π

          v = 2π /k  w /2π

           v = w / k

A certain dam generates 120 MJ of mechanical (hydroelectric) energy each minute. If the conversion from mechanical to electrical energy is then 15% efficient, what is the dam's electrical power output in W?

Answers

Answer:

electric energy ( power ) = 300000 W

Explanation:

given data

mechanical (hydroelectric) energy = 120 MJ/min = 2000000 J/s

efficiency = 15 % = 0.15

solution

we know that Efficiency of electric engine is expression  as

Efficiency = Mechanical energy ÷ electric energy  ......................1

and here dam electrical power output is

put here value in equation 1

electric energy ( power ) = Efficiency × Mechanical energy ( power )

electric energy ( power ) = 0.15 × 2000000 J/s

electric energy ( power ) = 300000 W

You walk into an elevator, step onto a scale, and push the "down" button to go directly from the tenth floor to the first floor. You also recall that your normal weight is w= 635 N. If the elevator has an initial acceleration of magnitude 2.45 m/s2, what does the scale read? Express your answer in newtons.

Answers

Answer: 479. 425 N

Explanation: the calculation of a body in an elevator obeys Newton law. When it is accelerating upward, the scale reading is greater than the true weight of the person.

It is given by N= m(g+a)

When it is accelerating downward, the scale reading is less than the true weight.

It so given by N = m(g-a)

The answer to the above questions is in the attached photo

Answer:

the scale will read 476.414 N

Explanation:

Weight = 635 N

mass = (weight) ÷ (acceleration due to gravity 9.81 m/^2)

mass m = 635 ÷ 9.81 = 64.729 kg

initial acceleration of the elevator a = 2.45 m/s^2

the force produced by the acceleration of the elevator downwards = ma

your body inertia force try to counteract this force, by a force equal and opposite to the direction of this force, leading to an apparent weight loss

apparent weight = weight - ma

apparent weight = 635 - (64.729 x 2.45)

apparent weight =  635 - 158.586  = 476.414 N


An ac circuit consist of a pure resistance of 10ohms is connected across an ae supply
230V 50Hz Calculate the:
(i)Current flowing in the circuit.

(ii)Power dissipated

Answers

Plz check attachment for answer.

Hope it's helpful

When moving to a new apartment, you rent a truck and create a ramp with a 244 cm long piece of plywood. The top of the moving ramp lies on the edge of the truck bed at a height of 115 cm. You load your textbooks into a wooden box at the bottom of the ramp (the coefficient of kinetic friction between the box and ramp is = 0.2). Then you and a few friends give the box a quick push and it starts to slide up the ramp. A) What angle is made by the ramp and the ground?B) Unfortunately, after letting go, the box only tables 80cm up the ramp before it starts coming back down! What speed was the box initially traveling with just after you stopped pushing it?

Answers

Answer:

A)    θ = 28.1º , B)         v = 2.47 m / s

Explanation:

A) The angle of the ramp can be found using trigonometry

         sin θ = y / L

         Φ = sin⁻¹ y / L

         θ = sin⁻¹ (115/244)

         θ = 28.1º

B) For this pate we can use the relationship between work and kinetic energy

       W =ΔK

where the work is

       W = -fr x

the negative sign is due to the fact that the friction force closes against the movement

Lavariacion of energy cineta is

         ΔEm = ½ m v² - mgh

        -fr x = ½ m v² - m gh

the friction force has the equation

         fr = very N

           

at the highest part there is no speed and we take the origin from the lowest part of the ramp

To find the friction force we use Newton's second law. Where one axis is parallel to the ramp and the other is perpendicular

             

Axis y . perpendicular

            N- Wy = 0

            cos tea = Wy / W

            Wy = W cos treaa

             N = mg cos tea

we substitute

   

- (very mg cos tea) x = ½ m v²2 - mgh

            v2 = m (gh- very g cos tea x)

   let's calculate

           v = Ra (9.8 0.80 - 0.2 9.8 0.0 cos 28.1)

           v = RA (7.84 -1.729)

           v = 2.47 m / s

What is the relationship between the magnitudes of the collision forces of two vehicles, if one of them travels at a higher speed?

Answers

Explanation:

The collision forces are equal and opposite.  Therefore, the magnitudes are equal.

Check Your UnderstandingSuppose the radius of the loop-the-loop inExample 7.9is 15 cm and thetoy car starts from rest at a height of 45 cm above the bottom. What is its speed at the top of the loop

Answers

Answer:

v = 1.7 m/s

Explanation:

By applying conservation of energy principle in this situation, we know that:

Loss in Potential Energy of Car = Gain in Kinetic Energy of Car

mgΔh = (1/2)mv²

2gΔh = v²

v = √(2gΔh)

where,

v = velocity of car at top of the loop = ?

g = 9.8 m/s²

Δh = change in height = 45 cm - Diameter of Loop

Δh = 45 cm - 30 cm = 15 cm = 0.15 m

Therefore,

v = √(2)(9.8 m/s²)(0.15 m)

v = 1.7 m/s

The pressure exerted by a phonograph needle on a record is surprisingly large. If the equivalent of 0.600 g is supported by a needle, the tip of which is a circle 0.240 mm in radius, what pressure is exerted on the record in N/m2?

Answers

Answer:

[tex]P=3.25x10^{4}\frac{N}{m^2}[/tex]

Explanation:

Hello,

In this case, since pressure is defined as the force applied over a surface:

[tex]P=\frac{F}{A}[/tex]

We can associate the force with the weight of the needle computed by using the acceleration of the gravity:

[tex]F=0.600g*\frac{1kg}{1000g}*9.8\frac{m}{s^2} =5.88x10^{-3}N[/tex]

And the area of the the tip (circle) in meters:

[tex]A=\pi r^2=\pi (0.240mm)^2=\pi (0.240mm*\frac{1m}{1000mm} )^2\\\\A=1.81x10^{-7}m^2[/tex]

Thus, the pressure exerted on the record turns out:

[tex]P=\frac{5.88x10^{-3}N}{1.81x10^{-7}m^2} \\\\P=3.25x10^{4}\frac{N}{m^2}[/tex]

Which is truly a large value due to the tiny area on which the pressure is exerted.

Best regards.

Based on what you know about electricity, hypothesize about how series resistors would affect current flow. What would you expect the effective resistance of two equal resistors in series to be, compared to the resistance of a single resistor?

Answers

Answer:

Effective resistance of two equal resistors in series is twice that of a single resistor and in essence will reduce the amount of current flowing in the circuit.

Explanation:

When two resistors are connected in series, their effective resistance is the sum of their individual resistances. For example, given two resistors of resistance values R₁ and R₂, their effective resistance, Rₓ is given by;

Rₓ = R₁ + R₂            --------------(1)

If these resistors have equal resistance values, say R, then equation 1 becomes;

Rₓ = R + R

Rₓ = 2R

This means that their effective resistance is twice of their individual resistances. In other words, when two equal resistors are in series, their effective resistance is twice the resistance of each single one of those resistors.

Now, according to Ohm's law, voltage(V) is the product of current (I) and resistance (R). i.e

V = IR

I = [tex]\frac{V}{R}[/tex]

We can deduce that current increases as resistance decreases and vice-versa.

So, if the two equal resistors described above are connected in series, the amount of current flowing will be reduced compared to having just a single resistor.

An electric heater is constructed by applying a potential different of 120V across a nichrome wire that has a total resistant of 8 ohm .the current by the wire is

Answers

Answer:

15amps

Explanation:

V=IR

I=V/R

I = 120/8

I = 15 amps

what tools use cut wood

Answers

Answer:

hand saws

power saws

Circular Saw

Explanation:

that is all that i know

Bromine, a liquid at room temperature, has a boiling point

Answers

Yes it does !  The so-called "boiling point" is the temperature at which Bromine liquid can change state and become Bromine vapor, if enough additional thermal energy is provided.  The boiling point is higher than room temperature.

A particle of charge = 50 µC moves in a region where the only force on it is an electric force. As the particle moves 25 cm, its kinetic energy increases by 1.5 mJ. Determine the electric potential difference acting on the partice​

Answers

Answer:

nvbnncbmkghbbbvvvvvvbvbhgggghhhhb

Approximately what applied force is needed to keep the box moving with a constant velocity that is twice as fast as before? Explain

Answers

Complete question:

A force F is applied to the block as shown (check attached image). With an applied force of 1.5 N, the block moves with a constant velocity.

Approximately what applied force is needed to keep the box moving with a constant velocity that is twice as fast as before? Explain

Answer:

The applied force that is needed to keep the box moving with a constant velocity that is twice as fast as before, is 3 N

Force is directly proportional to velocity, to keep the box moving at the double of initial constant velocity, we must also double the value of the initially applied force.

Explanation:

Given;

magnitude of applied force, F = 1.5 N

Apply Newton's second law of motion;

F = ma

[tex]F = m(\frac{v}{t} )\\\\F = \frac{m}{t} v\\\\Let \ \frac{m}{t} \ be \ constant = k\\F = kv\\\\k = \frac{F}{v} \\\\\frac{F_1}{v_1} = \frac{F_2}{v_2}[/tex]

The applied force needed to keep the box moving with a constant velocity that is twice as fast as before;

[tex]\frac{F_1}{v_1} = \frac{F_2}{v_2} \\\\(v_2 = 2v_1, \ and \ F_1 = 1.5N)\\\\\frac{1.5}{v_1} = \frac{F_2}{2v_1} \\\\1.5 = \frac{F_2}{2}\\\\F_2 = 2*1.5\\\\F_2 = 3 N[/tex]

Therefore, the applied force that is needed to keep the box moving with a constant velocity that is twice as fast as before, is 3 N

Force is directly proportional to velocity, to keep the box moving at the double of initial constant velocity, we must also double the value of the applied force.

The cost of energy delivered to residences by electrical transmission varies from $0.070/kWh to $0.258/kWh throughout the United States; $0.110/kWh is the average value.

Required:
At this average price, calculate the cost of:

a. leaving a 40-W porch light on for two weeks while you are on vacation?
b. making a piece of dark toast in 3.00 min with a 970-W toaster
c. drying a load of clothes in 40.0 min in a 5.20 x 10^3-W dryer.

Answers

Answer:

Cost = $ 1.48

Cost = $ 0.005

Cost = $ 0.38

Explanation:

given data

electrical transmission varies = $0.070/kWh to $0.258/kWh

average value = $0.110/kWh

solution

when leaving a 40-W porch light on for two weeks while you are on vacation so cost will be

first we get here energy consumed that is express as

E = Pt    .................1

here E is Energy Consumed and Power Delivered is P and t is time

so power is here 0.04 KW and t = 2 week = 336 hour

so

put value in 1 we get

E = 0.04 × 336

E = 13.44 KWh

so cost will be as

Cost = E × Unit Price    .............2

put here value and we get

Cost = 13.44 × 0.11

Cost = $ 1.48

and

when you making a piece of dark toast in 3.00 min with a 970-W toaster

so energy consumed will be by equation 1 we get

E = Pt

power is = 0.97 KW and time = 3 min = 0.05 hour

put value in equation 1 for energy consume

E = 0.97 × 0.05 h

E = 0.0485 KWh

and we get cost by w\put value in equation 2 that will be

cost =  E × Unit Price

cost = 0.0485 × 0.11

Cost = $ 0.005

and

when drying a load of clothes in 40.0 min in a 5.20 x 10^3-W dryer

from equation 1 we get energy consume

E = Pt

Power Delivered = 5.203 KW and time = 40 min = 0.67 hour

E = 5.203 × 0.67

E = 3.47 KWh

and

cost will by put value in equation 2

Cost = E × Unit Price

Cost = 3.47 × 0.11

Cost = $ 0.38

A wheel starts from rest and rotates with constant angular acceleration to reach an angular speed of 12.9 rad/s in 2.98 s.
(a) Find the magnitude of the angular acceleration of the wheel.
(b) Find the angle in radians through which it rotates in this time interval.

Answers

Explanation:

(a) Find the magnitude of the angular acceleration of the wheel.

angular acceleration = angular speed /timeangular acceleration = 12.9/2.98 = 4.329rad/s²

(b) Find the angle in radians through which it rotates in this time interval.

angular speed = 2x3.14xf12.9rad = 2 x3.14

rad = 6.28/12.9rad = 0.487

Now we convert rad to angle

1 rad = 57.296°0.487 = unknown angleunknown angle =57.296 x 0.487 = 27.9°

The angle in radians = 27.9°

A passenger jet flies from one airport to another 1,233 miles away in 2.4 h. Find its average speed. = ____ m/s

Answers

Speed = (distance) / (time)

Speed = (1,233 mile) / (2.4 hour)

Speed = 513.75 mile/hour

Speed = (513.75 mi/hr) x (1609.344 meter/mi) x (1 hr / 3600 sec)

Speed = (513.75 x 1609.344 / 3600) (mile-meter-hour/hour-mile-second)

Speed = 229.7 meter/second

When you are told that the wind has a "Small Coriolis force" associated with it, what is that "small force" exactly

Answers

Answer:

Coriolis force is a type of force of inertia that acts on objects that is in motion within a frame of reference that rotates with respect to an inertial frame. Due to the rotation of the earth, circulating air is deflected result of the Coriolis force, instead of the air circulating between the earth poles and the equator in a straight manner. Because of the effect of the Coriolis force,  air movement deflects toward the right in the Northern Hemisphere and toward the left in the Southern Hemisphere, eventually taking a curved path of travel.

An accelerating voltage of 2.25 103 V is applied to an electron gun, producing a beam of electrons originally traveling horizontally north in vacuum toward the center of a viewing screen 36.4 cm away. (a) What is the magnitude of the deflection on the screen caused by the Earth's gravitational field

Answers

Answer:

s= 8.28×10⁻¹⁶m

Explanation:

given

V= 2.25×10³V

from conservation of energy

mv²/2=qΔV

v=√(2qΔV/m)

v= √(2×1.6×10⁻¹⁹×2.25×10³/9.1×10⁻³¹)

=√7.9×10¹⁴m/s

=2.8×10⁷m/s

the deflection of electron beam is

S= gt²/2

recall t= d/v

s=g([tex]\frac{d}{v}[/tex])²/2

s= [tex]\frac{1}{2}[/tex]×9.8×(0.364/2.8×10⁷)²

s= 8.28×10⁻¹⁶m

If you could see stars during the day, this is what the sky would look like at noon on a given day. The Sun is near the stars of the constellation Gemini. Near which constellation would you expect the Sun to be located at sunset?

Answers

Answer:

The sun will be located near the Gemini constellation at sunset

what is thermodynamic?​

Answers

Answer:

Thermodynamics is a branch of physics which deals with the energy and work of a system. It was born in the 19th century as scientists were first discovering how to build and operate steam engines. Thermodynamics deals only with the large scale response of a system which we can observe and measure in experiment.

Answer:

thermodynamics is the branch of physics which deals with the study of heat and other forms energy and their mutual relationship(relation ship between them)

Explanation:

i hope this will help you :)

describe the relation among density, temperature, and volume when the pressure is constant, and explain the blackbody radiation curve

Answers

Answer:

in all cases with increasing temperature the density should decrease.

Black body radiation is a construction that maintains a constant temperature and a hole is opened, this hole is called a black body,

Explanation:

Let's start for ya dream gas

        PV = nRT

Since it indicates that the pressure is constant, we see that the volume is directly proportional to the temperature.

The density of is defined by

        ρ = m / V

As we saw that volume increases with temperature, this is also true for solid materials, using linear expansion. Therefore in all cases with increasing temperature the density should decrease.

Black body radiation is a construction that maintains a constant temperature and a hole is opened, this hole is called a black body, since all the radiation that falls on it is absorbed or emitted.

This type of construction has a characteristic curve where the maximum of the curve is dependent on the tempera, but independent of the material with which it is built, to explain the behavior of this curve Planck proposed that the diaconate in the cavity was not continuous but discrete whose energy is given by the relationship

             E = h f

A d'Arsonal meter with an internal resistance of 1 kohm requires 10 mA to produce full-scale deflection. Calculate thew value of a series

Answers

Question:

A d’Arsonval meter with an internal resistance of 1 kΩ requires 10 mA to produce full-scale deflection. Calculate the value of a series resistance needed to measure 50 V of full scale.

Answer:

4kΩ

Explanation:

Given;

internal resistance, r = 1kΩ

current, I = 10mA = 0.01A

Voltage of full scale, V = 50V

Since there is full scale voltage of 50V, then the combined or total resistance (R) of the circuit is given as follows;

From Ohm's law

V = IR

R = [tex]\frac{V}{I}[/tex]                 [substitute the values of V and I]

R = [tex]\frac{50}{0.01}[/tex]

R = 5000Ω = 5kΩ

The combined resistance (R) is actually the total resistance of the series arrangement of the series resistance([tex]R_{S}[/tex]) and the internal resistance (r) in the circuit. i.e

R = [tex]R_{S}[/tex] + r

[tex]R_{S}[/tex] = R - r                 [Substitute the values of R and r]

[tex]R_{S}[/tex] = 5kΩ - 1kΩ

[tex]R_{S}[/tex] = 4kΩ

Therefore the series resistance is 4kΩ

Stress is a factor that contributes to heart disease risk.true or false

Answers

The answer for this question would be True

A uniform 2.0-kg rod that is 0.92 m long is suspended at rest from the ceiling by two springs, one at each end. Both springs hang straight down from the ceiling. The springs have identical lengths when they are unstretched. Their spring constants are 29 N/m and 66 N/m. Find the angle that the rod makes with the horizontal.

Answers

Answer:

11.7°

Explanation:

See attached file

You illuminate a slit with a width of 77.7 μm with a light of wavelength 721 nm and observe the resulting diffraction pattern on a screen that is situated 2.83 m from the slit. What is the width, in centimeters, of the pattern's central maximum

Answers

Answer:

The width is  [tex]Z = 0.0424 \ m[/tex]

Explanation:

From the question we are told that

    The width of the slit is [tex]d = 77.7 \mu m = 77.7 *10^{-6} \ m[/tex]

    The wavelength of the light is  [tex]\lambda = 721 \ nm[/tex]

      The position of the screen is  [tex]D = 2.83 \ m[/tex]

Generally angle at which the first minimum  of the interference pattern the  light occurs  is mathematically  represented as

        [tex]\theta = sin ^{-1}[\frac{m \lambda}{d} ][/tex]

Where m which is the order of the interference is 1

substituting values

       [tex]\theta = sin ^{-1}[\frac{1 *721*10^{-9}}{ 77.7*10^{-6}} ][/tex]

      [tex]\theta = 0.5317 ^o[/tex]

 Now the width of first minimum  of the interference pattern is mathematically evaluated as

       [tex]Y = D sin \theta[/tex]

substituting values

       [tex]Y = 2.283 * sin (0.5317)[/tex]

       [tex]Y = 0.02 12 \ m[/tex]

 Now the width of  the  pattern's central maximum is mathematically evaluated as

        [tex]Z = 2 * Y[/tex]

substituting values

      [tex]Z = 2 * 0.0212[/tex]

     [tex]Z = 0.0424 \ m[/tex]

What is meant civilized?

Answers

Answer:

at an advanced stage of social and cultural development. "a civilized society"

Explanation:

polite and well-mannered "I went to talk to them and we had a very civilized conversation" hope this helps you :)

When the charges in the rod are in equilibrium, what is the magnitude of the electric field within the rod?

Answers

Answer: If we have equilibrium, the magnitude must be zero.

Explanation:

If the charges are in equilibrium, this means that the total charge is equal to zero.

And as the charges must be homogeneously distributed in the rod, we can conclude that the electric field within the rod must be zero, so the magnitude of the electric field must be zero

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How large a sample should be taken if the desired margin of error is as shown below (to the nearest whole number)?1. $500?2. $200?3. $100? Coach kunal stacks all of the tennis balls in a square pyramid. The number of tennis balls, P(n), in n layers of the square pyramid is given by P(n) = P(n - 1) + n^2. Which could not be the number of tennis balls Coach Kunal has? A. 30 B. 5 C. 14 D. 9 Rewrite the expression in the form k x z^n . A Solutions Architect needs to build a resilient data warehouse using Amazon Redshift. The Architect needs to rebuild the Redshift cluster in another region. Which approach can the Architect take to address this requirement how does the media control the public agenda and what people care about? what is one danger that is posed by a for-profit corporation setting the public agenda ? What action would cause a historian to be accused of plagiarism?O A. Copying into an essay information from a secondary sourcewithout citing itB. Refuting counterclaims in the body paragraphs of anargumentative essayO C. Including a comprehensive works-cited list at the end of anexplanatory essayD. Failing to include an introduction or conclusion paragraph in anessay En una fiesta se desea elegir un grupo de 3 personas de entre 6 matrimonios, si dos miembros de la misma pareja no pueden ser elegidos para formar parte de ese grupo. De cuantas maneras diferentes se puede formar el grupo de 3 personas? Gold standard required countries to A. keep the supply of foreign exchange less than their domestic money supply. B. restrict the demand for foreign goods. C. keep the supply of their domestic money constant. D. keep the supply of their domestic money fixed in proportion to their gold holdings. A tourist can bicycle 28 miles in the same time as he can walk 8 miles. If he can ride 10 mph faster than he can walk, how much time (in hr) should he allow to walk a 25-mile trail? (Hint: How fast can he walk?) ________ hr. (enter a fraction) Assume that you are 30 years old today, and that you are planning on retirement at age 65. You expect your salary to be $42,000 one year from now and you also expect your salary to increase at a rate of 5% per year as long as you work. To save for your retirement, you plan on making annual contributions to a retirement account. Your first contribution will be made on your 31st birthday and will be 8% of this year's salary. Likewise, you expect to deposit 8% of your salary each year until you reach age 65. Assume that the rate of interest is 9%. The present value (PV) (at age 30) of your retirement savings is closest to You are interested in becoming more physically fit, but you find yourself making excuses to get out of jogging most afternoons. What can you do to improve your interest in completing the necessary amount of physical activity each day? A: Set an alarm to make sure you know it is time to go jogging B: Try different activities to find something you enjoy more C: Jog alone so you can end the workout early if you get bored D: Fill your schedule with other activities so you don't have time to jogPlease help me, im struggling and i feel so dumb.. :( I will give you extra points and name your answer as the brainliest :) Type the correct answer in each box, If necessary, use / for the fraction bar(s).1-1The point on the number line shows the opposite ofor the opposite of the opposite ofResetNext Help help help please I need help fast