A flat polished area is turned through 15 degrees. If the angle of incidence is 20 degrees, what is the angle between the incident ray and the reflected ray of the turned surface?

Answers

Answer 1

Answer:

50°

Explanation:

Angle of rotation of the flat polished surface [tex]\theta[/tex] = 15°

angle of incidence i = 20°

Since the polished surface is turned at an angle of 15°, the angle of reflection

r = 2[tex]\theta[/tex] (Note that the angle of rotation only have effect of the angle of reflection)

r = 2*15 = 30°

The angle between the reflected ray and the incident ray will be equal to the sum of the angle of incidence and the angle of reflection i.e i+r

The angle between the reflected ray and the incident ray = 20°+ 30° = 50°


Related Questions

A vehicle traveling on wet or slick roads can begin to _________ as water forms a barrier between the road and the tires and traction is lost as the wheels start to ride on top of the water and not the road surface. a) skid b) hydroplane c) lose traction d) splash water on to the engine

Answers

Answer: B.) HYDROPLANE

Explanation: The term hydroplane can be used to refer to a condition which usually occur during a downpour or on surfaces covered by water. It occurs when water forms a barrier or comes in between the frictional grip which occurs between the road surface and the car tyres. The contact between the car tyres and the road surface is supposed to give adequate frictional support which prevents the car from skidding or skidding uncontrollably on the road surface. However, when water comes invetween the surface, traction is lost and skidding results due to very low Coefficient of friction between the road and Tyre which was supposed to provide a firm grip between the tyres and the road surface.

When a vehicle is traveling on wet or slick roads, hydroplaning can occur. The correct answer is b) hydroplane.

When a vehicle is traveling on wet or slick roads, hydroplaning can occur. Hydroplaning happens when a layer of water builds up between the tires of the vehicle and the road surface, leading to a loss of traction.

This loss of traction can cause the vehicle to skid or slide, making it difficult to control. The tires ride on top of the water rather than maintaining contact with the road, resulting in reduced traction and control of the vehicle.

Therefore, When a vehicle is traveling on wet or slick roads, hydroplaning can occur. The correct answer is b) hydroplane.

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If you hold a bar magnet in each hand and bring your hands together, will the force be attractive or repulsive if the magnets are held:
a) with the two north poles together?
b) with a north pole and south pole together

Answers

Answer:

Part A:

They will repel each other because same poles repel each other.

Part B)

They will attract each other because different poles attract each other..

Evelyn walked to the store a distance of 1.6 km in 30 min. What is her average speed in m/s?

Answers

Average speed = (distance covered) / (time to cover the distance)

Average speed = (1.6 km) / (30 min)

Average speed = 0.0533 km/min

This is the true average speed, but it's not in the units that the question asked for.  So we have to massage it and convert it to ' meters/sec '.

Speed = (1.6 km) / (30 min)

Speed = (1.6 km / 30 min) x (1,000 m / 1 km) x (1 min / 60 sec)

Speed = (1.6 x 1,000 x 1) / (30 x 1 x 60) (km-m-min / min-km-sec)

Speed = (1,600 / 1,800) (m / sec)

Speed = 0.89 m/s    

Three 15.0-W resistors are connected in parallel across a 30.0-V battery. Please show all work.
a) Find the current through each branch of the circuit.
b) Find the equivalent resistance of the circuit.
c) Find the current through the battery.

Answers

Answer:

Part A)

Since all of the resistors have equal resistance, hence for finding even only 1 branch It will be fine because current will be the same for all branches.

=> [tex]I = \frac{V}{R_{1} }[/tex]

=> [tex]I = \frac{30}{15}[/tex]

=> I = 2 A

Part B)

Equivalent resistance for parallel circuits is the sum of reciprocals of each resistor.

=> [tex]\frac{1}{R} = \frac{1}{R_{1}}+\frac{1}{R_{2}} +\frac{1}{R_{3}}[/tex]  

=> [tex]\frac{1}{R} = \frac{1}{15}+ \frac{1}{15}+\frac{1}{15}[/tex]

=> [tex]\frac{1}{R} = \frac{3}{15}[/tex]

=> R = 15/3

=> R = 5 ohms

Part C)

I = V/R

Where I is current, V is voltage and R is the equivalent resistance

=> I = 30/5

=> I = 6 A

A 17-tooth spur pinion has a diametral pitch of 8 teeth/in, runs at 1016 rev/min, and drives a gear at a speed of 508 rev/min. Find the number of teeth on the gear and the theoretical center-to-center distance.

Answers

This should be easy bae or skip it ! 900x65=22

Average acceleration. Please help!

Answers

Answer:

8.43 m/s²

Explanation:

Average acceleration is the change in velocity over change in time.

a = Δv/Δt

First, convert km/h to m/s.

45 km/h = 12.5 m/s

500 km/h = 138.9 m/s

Now find the acceleration.

a = (138.9 m/s − 12.5 m/s) / 15.0 s

a = 8.43 m/s²

give four example each for newton's first,second,and thirdlaw of motion​

Answers

1st: [An airplane midflight] will maintain its direction unless maneuvered by a pilot
Kicking a ball. Driving a car, any stationary object.
2nd: [Pushing a box] the more force you put into moving the box the faster the box will move.
Ball rolling down a hill, riding a bike, batting a ball
3rd: [Jumping] your feet push against the ground
Moving car, running into a wall, paddling

Which of these results in kinetic energy of an object? a position b motion c mass d volume

Answers

Answer:

Option B

Explanation:

Kinetic Energy is the energy possessed by the body due to "motion".

The answer is:

B. Motion

Q- A body is acted upon by two forces 30N due east and 40N due North. Calculate
resultant and its direction. ​

Answers

Answer:

the following image will make you understand

Explanation:

write a story that ends with poor no friend​

Answers

Answer:

Writing of a story that ends with the character becoming poor with no friends.

Explanation:

There was a young girl who believed that all things revolve around her. She had the money, the power, the family, and the beauty to ensure she was the center of attention. She would always be the main focus, everywhere she goes.

But there came a time when she had a major misfortune. Her family had come upon unfortunate times. They are going to lose their money and may even be jailed for embezzlement. It was true that she had no idea what her parents had done but she was also so familiar with the 'princess' lifestyle that she did not know how to downgrade her lifestyle. And so, when this misfortune happened, she was unsure how to react. She also assumed that her friends will be there for her. Little did she know everyone was just after her wealth and influence and had nothing to do with genuine friendship.

In a few months, their family position moved from top to bottom, which everyone found hard to accept. She had to maintain her status while at the same time try to live up with that without losing her circle. But as rumors spread fast and she wasn't able to spend the way she would normally send, she eventually experienced a dwindled friend circle. And in about a year, she had lost all of her friends, couldn't even convince someone to stay with her faithfully and worse of all, she was also poor, the very status she had degradingly taunted other people with.

a boy runs from his house to school at speed 5m/s on a straight road and returns with speed of 10m/s.The distance between the house and school is 100m. Find his average velocity.... with explaination please​

Answers

Explanation:

time spent to run from house to school=100/5=20s

time spent to return from school=100/10=10s

average velocity=200m/(10+20)

=6.66m/s

Explain the concept of "charge" and how it relates to electricity?

Answers

Answer:

An Electric "charge" is a property of matter that causes a force to repel or attract when placed into a magnetic field. These charges can be replicated into positive and negative electrons when made from a chemical reaction.

Answer:

an electri

Explanation:

On which body would a 10 kg lamp have the most gravitational potential energy when lifted to height of 2 m? A) Earth B) Mars C) Neptune D) Uranus

Answers

Answer: C.) Neptune

Explanation:

The Gravitational Potential Energy (GPE) of a body is calculated using the formula :

GPE = mgh

Where m = mass of the body

g = acceleration due to gravity

h = distance above a surface

Mass = 10kg

h = 2m

Using the formula :

GPE of lamp on Earth: g = 9.8

GPE = 10 × 9.8 × 2 = 71.8J

GPE of lamp on Mercury: g = 3.59

GPE = 10 × 3.59 × 2 = 196J

GPE of lamp on Mars: g = 3.7

GPE = 10 × 3.7 × 2 = 74J

GPE of lamp on Neptune: g = 14.07

GPE = 10 × 14.07 × 2 = 281.4J

GPE of lamp on Uranus: g = 9

GPE = 10 × 9 × 2 = 180J

GPE of lamp on Pluto: g = 0.42

GPE = 10 × 0.42 × 2 = 8.4J

Neptune has the highest gravitational potential energy as the value of acceleration due to gravity acting on objects is highest on Neptune.

Answer:

The correct option is;

C) Neptune

Explanation:

The force of gravity is given by the equation;

[tex]F_g = G\dfrac{m_1m_2}{r^2} = m_2 \times g[/tex]

Where:

m₁ = Mass of the planet

m₂ = Mass of the body = 10 kg

r = The distance between the body and the planet = 2 m

g = Gravitational acceleration on the planet

G = Gravitational constant

Given that the potential energy, PE = m × g × h

We have that,

[tex]PE = m_2 \times g \times (r + 2) = G\dfrac{m_1m_2}{r^2} \times (r + 2) \approx G\dfrac{m_1m_2}{r^2} \times r = G\dfrac{m_1m_2}{r}[/tex]

Therefore, the gravitational potential energy is directly proportional to the acceleration of gravity, such that the body will have the most gravitational potential energy in the planet with the highest acceleration due to gravity which is Neptune with acceleration due to gravity of 14.07 m/s².

PLZ HELP What is necessary condition for production of waves?

Answers

Answer:

The length of the rope must be an integral multiple of the wavelength of the wave.

Explanation:

Answer:

The condition necessary for formation or a standing wave is that the length of the rope (or the length over which the wave is distributed) must be an integral multiple of the wavelength of the wave. Therefore, l=nλ where n is a positive integer.

any ss2 here (11th Grade)

Answers

Answer:

a) 50°b) 40°

Explanation:

Check the complete diagram n the attachment below

a) The angle of incidence on a plane surface is the angle between the incidence ray and the normal ray acting on a plane surface. The normal ray is the ray perpendicular to the surface while the incidence ray is the ray striking a plane surface.

According to the diagram, the angle of reflection r₂ on M₂ is 90°-g where g is the angle of glance.

Given angle of glance on M₂ to be 40°, r₂ = 90-40 = 50°

According the second law of reflection, the angle of incidence = angle of reflection, therefore i₂ = r₂ = 50° (on M₂)

Also ∠OO₂O₁ =  ∠OO₁O₂ = 40° (angle of glance on M){alternate angle}

The angle of incidence on M₁ = 90° - 40° = 50°

b) The angle of incidence to the surface of M₁(∠PO₁A)will be the angle of glance on M₁ which is equivalent to 40°

A car of mass 800 kg is moving at a uniform velocity of 72 km/hr. Find its
momentum.
[Ans: 16000 kgm/s)
A body of mass 5 kg has momentum of 125 kg m/s. Find the velocity of the body
in motion.
[Ans: 25 mls)​

Answers

Answer:

hope its helpful to uh...

What is the net force acting on the buggy. ?The net force is pointing to the ?

Answers

Answer: 390, right

explanation: The net force is just the sum of all of these forces acting on an object. ... This equation is the sum of n forces acting on an object. The magnitude of the net force acting on an object is equal to the mass of the object multiplied by the acceleration of the object, as shown in this formula.

the net force acting on the buggy is 390 and The net force is pointing to the is right

The following information should be considered:

The net force should be the sum of all of these forces that acted an object.This equation is the sum of n forces acting on an object. The magnitude of the net force acting on an object is equivalent to the mass of the object and multiplied by the acceleration of the object

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We weigh less in water than in air. Why? ​

Answers

It is because of the buoyang force
We actually are the same weight as they are on dry land due to gravity acting at a constant acceleration on the mass of the object. Objects due however "appear" to weigh less in water. This is due to what is known as buoyancy. Buoyancy is actually the upward force of a liquid acting on an object that is placed in it.

state any two physical properties for believing that aluminium is a metal.​

Answers

Answer:

amongst the properties that makes aluminium a metal is that it is malleable and ductile...and it has high melting and boiling points

I hope that helps

Explanation:

properties of metals include

1. high melting and boiling points

2 high densities

3 malleability and ductility

a body starts from rest and gains the velocity of 5 metre per second into second is it of uniform velocity explain​

Answers

Answer:

It is not a uniform velocity, because his velocity increases for 5 m every second (acceleration = 5m/s2), meaning his velocity always changes.

When he starts at rest, his velocity is 0 m/s. But in 1 second later, his velocity is already 5m/s. At 2 seconds, his velocity will be 10 m/s.

PLZ HELP Sound is a form of wave. List at least three reasons to support the idea that sound is a wave

Answers

Answer:

Sound is a form of wave . Wave is defined as a periodic disturbance in medium.

Reasons:  

1. It follows all properties of light at a boudary.

2. Noise cancelling headphones.

3. It carry energy from one place to another.

Explanation:

I hope this will help you guy.

Sound wave is a mechanical type of wave because it requires a material medium for its propagation.

The following are three reasons sound is classified as a wave.

Reflection: sound waves are reflected like other waves when they strike a plane surface. This effect results to a phenomenon called Echo. Echo is the sound heard after the reflection of sound waves from a plane surface.Interference: sound wave like other form of wave exhibits interference. Interference of sound occurs when two waves of same frequency emitted by two close sources are superposed.Refraction: sound wave like other forms of wave also exhibits changes in  velocity, frequency and wavelength when it moves from one medium to another.  

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Which is a negative effect of deforestation on the environment? A. habitat restoration B. desertification C. soil production D. urbanization

Answers

Answer:Deforestation refers to the decrease in forest areas across the world that are lost for other uses such as agricultural croplands, urbanization, or mining activities. Greatly accelerated by human activities since 1960, deforestation has been negatively affecting natural ecosystems, biodiversity, and the climate. The UN’s Food and Agriculture Organization estimates the annual rate of deforestation to be around 1.3 million km2 per decade.

Explanation:

The negative effect of deforestation on the environment is desertification. The correct option is B.

What is desertification?

Desertification is the process by which fertile land becomes desert, typically as a result of drought, deforestation, and inappropriate agriculture or land use practices. It occurs when land that was once able to support vegetation and life becomes increasingly dry, barren, and unable to sustain crops, livestock, or human populations. This can be due to natural causes such as prolonged droughts, but it is often exacerbated by human activities such as deforestation, overgrazing, and soil degradation. Desertification can have devastating effects on the environment, leading to soil erosion, loss of biodiversity, and reduced productivity of the land. It can also cause social and economic problems, such as displacement of people, food shortages, and conflicts over resources.

Here in the question,

Deforestation is the clearing of trees and other vegetation from an area, leading to the loss of habitat and biodiversity, and disruption of water cycles. It can also cause soil erosion, which can result in the depletion of soil nutrients, reduced productivity, and eventually lead to desertification. Additionally, deforestation contributes to climate change by releasing carbon dioxide into the atmosphere, which can cause global warming and other environmental problems. Habitat restoration, soil production, and urbanization are not negative effects of deforestation but can be impacted by it.

Therefore, The correct answer is B i. e Desertification.

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HELP NEEDE ASAP!!!!!!!! How do you understand by the longitudinal wave? Describe the longitudinal nature of sound waves

Answers

Answer:

Sound as a Longitudinal Wave

For a sound wave traveling through air, the vibrations of the particles are best described as longitudinal. Longitudinal waves are waves in which the motion of the individual particles of the medium is in a direction that is parallel to the direction of energy transport.

Answer:

Hey!

Here is your answer!

Explanation:

LONGITUDINAL WAVES:

These are waves where the transferral of energy is PARALLEL to the direction it travels in...For Example...Sound Waves are Longitudinal as they move in a series of COMPRESSIONS and RAREFACTIONS (typical of all Longitudinal Waves)...

The compressions are known in diagrams to be an area of a dense collection of PARTICLES where the energy (or sound in this case) is being transferred in the same direction as the movement...

The rarefactions are shown as almost empty area of particles where the medium (the matter of which the wave travels in) is moving...

Hope this helps!

*here's a diagram*

Before beginning an experiment, Mrs. Wilson warns her science class not to drop the bar magnets on the floor. What is the most likely reason for Mrs. Wilson’s warning?

Answers

Answer:

we should not drop a magnet on the floor because the magnets tend to lose magnetism gradually and become weak over a period of time if they are not stored properly.

Answer:

Well depending on the floor like say if it was a wooden floor the magnet might lose it magnetism, if concrete floor the magnetic brake and still lose it magnetism, if a metal floor the magnet would stick not sure if it wood lose it magnetism or not but the possibilities still there, basically what I'm saying is the magnet would lose its magnetism if it were to interact with the floor maybe temporary or maybe permanently.

for those with with a learning disability it's a

Explanation:

A lightbulb is rated by the power that it dissipates when connected to a given voltage. For a lightbulb connected to 120 V household electricity, decreasing the resistance of the filament will _____ the current through the bulb and _____ the power dissipated by the bulb. A lightbulb is rated by the power that it dissipates when connected to a given voltage. For a lightbulb connected to 120 V household electricity, decreasing the resistance of the filament will _____ the current through the bulb and _____ the power dissipated by the bulb. Decrease, decrease Decrease, increase Increase, increase Increase, decrease

Answers

Answer:

Increases, increases

Explanation:

The current is directly proportional to the voltage and inversely proportional to the resistance. The implication of this is that, whenever the voltage is increased, the current increases simultaneously. On the other hand, if the resistance is increased, the current will decrease accordingly and vice versa.

Recall that power is given by P= V^2/R where;

P= power, V= voltage and R= resistance

We can see that power and resistance are inversely related hence decreasing the resistance increases the power output of the lightbulb.

Answer:

Increase, increase

Explanation:

Ohm's law states that R=V/I .

This can be rearranged as I = V/R , showing that current is inversely proportional to resistance. When resistance decreases, current increases (with constant voltage).

Power dissipated by a resistor is given by the equation P = RI^2 . Showing that as R decreases and increases I, the increase to I is exponential while the decrease in resistance is not, which leads to increased power dissipation.

1. Light from a laser shines through two narrow slits 0.300 mm apart and produces an interference pattern on a screen 4.35 m away consisting of 9 bright fringes over a distance of 6.4 cm. a) Draw a labeled diagram of this scenario and briefly explain how the interference pattern is created b) Calculate the wavelength of the laser. What color is it?

Answers

Answer:

Explanation:

slit separation d = .3 x 10⁻³ m

screen distance D = 4.35 m

fringe width = 6.4 x 10⁻² / 9

= .711 x 10⁻² m

a ) Interference pattern on the screen is created due to interference of two light waves coming from two slits and falling in screen . When they fall on different points on the screen they travel different distance . This is called path difference . When their path difference is equal to their wave length or its integral multiple , they reinforce each other and at that point the brightness increases . On the other hand when at a point the path difference is equal to odd multiple of half wavelength , they kill or destroy each other and darkness is found at that point . In this way dark band and bright band appear on the screen . This is called interference pattern .

b )

Fringe width  = λ D / d

Putting the values

.711 x 10⁻² = λ x 4.35 /  0.3 x 10⁻³

λ = .049 x 10⁻⁵

= 490 x  10⁻⁹

= 490 nm

The colour of this wavelength will be blue .

At one point in the rescue operation, breakdown vehicle A is exerting a force of 4000 N and breakdown vehicle B is exerting a force of 2000 N.(i) Using a scale of 1 cm = 500 N, make a scale drawing to show the resultant force on the truck. (ii) Use your diagram to find the magnitude and direction of the resultant force on the truck.

Answers

Answer:

1.) Magnitude = 5596 N

2.) Direction = 60 degrees

Explanation: You are given that the breakdown vehicle A is exerting a force of 4000 N at angle 45 degree to the vertical and breakdown vehicle B is exerting a force of 2000 N

Let us resolve the two forces into X and Y component

Sum of the forces in the X - component will be 4000 × cos 45 = 2828.43 N

Sum of the forces in the Y - component will be 2000 + ( 4000 × sin 45 )

= 2000 + 2828.43

= 4828.43 N

The resultant force R will be

R = sqrt ( X^2 + Y^2 )

Substitutes the forces at X component and Y component into the formula

R = sqrt ( 2828.43^2 + 4828.43^2 )

R = sqrt ( 31313752.53 )

R = 5595.87 N

The direction will be

Tan Ø = Y/X

Substitute Y and X into the formula

Tan Ø = 4828.43 / 2828.43

Tan Ø = 1.707106

Ø = tan^-1( 1.707106 )

Ø = 59.64 degree

Therefore, approximately, the magnitude and direction of the resultant force on the truck are 5596 N and 60 degree respectively.

as a motorcycle takes a sharp turn the type of motion that occurs is called ——— motion

Answers

Answer:

circular motion

Explanation:

hope this helps you :)

Answer:

Centripetal motion

Explanation:

As a motorcycle takes a sharp turn the type of motion that occurs is called centripetal motion

An airplane starts at rest and accelerates down the runway for 25 s. At the end of the runway, its final velocity is 75 m/s east. What is its acceleration?

Answers

Answer

3m/s²

Explanation

u=o

t=25s

v=75m/s

from Newton's first law of motion,

v=u+at

75=0+a(25)

75=25a

a= 75/25

a=3m/s²

The acceleration of the airplane is 3m/s².

What is acceleration?

Acceleration is rate of change of velocity with time. Due to having both direction and magnitude, it is a vector quantity. Si unit of acceleration is meter/second² (m/s²).

Given parameters:

Initial velocity of the airplane: u=o.

Time taken: t=25s.

Final velocity of the airplane: v=75m/s.

We have to find acceleration of the plane: a = ?

We know that for accelerating motion of the air plane; final velocity can be expressed as:

    v=u+at

⇒ 75=0+a(25)

⇒ 75=25a

⇒ a= 75/25

⇒ a= 3m/s².

hence, acceleration of the airplane is 3m/s².

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what is called gratational force

Answers

Answer:

Gravitational force can be seen as the pull that the earth has on an piece of matter. Everything on earth has a force acting on it which is gravity. It tries to pull two object closer to each other but never apart. The numerical value for gravitational force is 9.8 m/s^2 for free falling objects

Gravity, also called gravitation, in mechanics, the universal force of attraction acting between all matter. ... On Earth all bodies have a weight, or downward force of gravity, proportional to their mass, which Earth's mass exerts on them. Gravity is measured by the acceleration that it gives to freely falling objects.
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