A small hole P is made in a piece of cardboard. The hole is illuminated by a torch as shown in Fig. 16.3. The pencil of light coming out of the hole falls on a mirror.

5th question ​

Answer:

The frequency heard by the observer is 24,830.35 Hz.

Explanation:

Given;

frequency of the source, Fs = 18,002 Hz

speed of the source, Vs = 130

speed of sound in air, V = 343 m/s

Apply Doppler effect, as the source and the observer move closer to each other, the frequency heard by the observer increases because of decrease in distance.

[tex]f_s = f_o[\frac{v}{v + v_s} ]\\\\[/tex]

where;

f₀ is the frequency heard by the observer

[tex]f_s = f_o[\frac{v}{v + v_s} ]\\\\18,002 = f_o[\frac{343}{343 + 130} ]\\\\18,002 = f_o(0.725)\\\\f_o = \frac{18,002}{0.725} \\\\f_o = 24,830.35 \ Hz[/tex]

Therefore, the frequency heard by the observer is 24,830.35 Hz.

Answer: [tex]_8^{15}\textrm{O}\rightarrow _{7}^{15}\textrm{N}+_{+1}^0{e}[/tex]

Explanation:

Positron emission: In this process, in which a proton inside a radionuclide nucleus is converted into a neutron while releasing a positron and an electron neutrino. The beta positive particle released is basically a positron with +1 charge and no mass.

General representation of an element is given as:  

[tex]_Z^A\textrm{X}\rightarrow _{Z+1}^A\textrm{Y}+_{+1}^0{e}[/tex]

where,

Z represents Atomic number

A represents Mass number

X and Y represents the symbol of an element

For [tex]_8^{15}\textrm{O}\rightarrow _{7}^{15}\textrm{N}+_{+1}^0{e}[/tex]

Answer:

B. older than 50,000 years old

hope it helps you

Rocks older than 50,000 years old are objects in which geologists use carbon-14 dating to determine its age.

This is used to determine age by using the decay to nitrogen of radiocarbon (carbon-14).

Older rocks can have its age determined through the use of carbon-14 which is why option B was chosen.

Read more about Carbon dating here https://brainly.com/question/1122575

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Answer:

.

Explanation:

Answer:

B. Atoms and their electrons are rearranged.

D. The elements stay the same.

Answer:

3.88 × 10^-4 m

Explanation:

Given that a  person who weighs 614 N is riding a 85-N mountain bike. Suppose the entire weight of the rider plus bike is supported equally by the two tires. If the gauge pressure in each tire is 9.00 x 10^5 Pa. What is the area of contact between each tire and the ground?

The total weight = 614 + 85

The total weight = 699N

Let the total area of contact = A

Pressure = Force / A

Substitute all the parameters into the formula

900000 = 699 /A

A = 699 / 900000

A = 7.77 × 10^-4 m

The area of contact between each tire and the ground will be = A/2

That is, 7.77 / 2 = 3.88 × 10^-4 m

Therefore, the area of contact between each tire and the ground is 3.88 × 10^-4 m approximately.

Answer:

0.159

Explanation:

Given that

F1 = 440 N

F2 = 340 N

m = 500 kg

acceleration, a = 0 m/s²

Remember that F = m.a

If F - f(f) = 0, then F = f(f)

N = mg

f(f) = μN, substituting for N, we have

f(f) = μmg

The total force, F = F1 + F2

F = 440 + 340

F = 780 N

Recall that we'd already proven that

F = f(f), so F = 780 N = f(f)

And again, f(f) = μmg, if we substitute for all the values, we have

780 = μ * 500 * 9.81

780 = μ * 4905

μ = 780 / 4905

μ = 0.159

Therefore, the coefficient of static friction of the crate on the floor is 0.159

The required average speed of bicycle rider is 12 km/h.

Given data:

The distance travelled by the bicycle rider is, d = 15 km.

Time taken to cover the distance is, t = 1.25 h.

Here, we need to use the simple relation between the speed, time and distance. The distance covered covered by any object per unit of time is known as average speed of object. And the mathematical expression for the average speed is given as,

[tex]v = \dfrac{d}{t}[/tex]

Here, v is the average speed.

Solving as,

[tex]v = \dfrac{15}{1.25}\\\\v = 12\;\rm km/h[/tex]

Thus, we can conclude that the required average speed of bicycle rider is 12 km/h.

Learn more about the average speed here:

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Answer:

108.33 grams.

Explanation:

Given that,

Mass of a egg, m = 65 g

Volume of an egg, V = 60 cc

We need to find the mass of the salt dissolved in 100cc of water so that egg just float in water.

The density will remains constant,

[tex]\dfrac{m_1}{V_1}=\dfrac{m_2}{V_2}\\\\m_2=\dfrac{m_1V_2}{V_1}\\\\m_2=\dfrac{65\times 100}{60}\\\\=108.33\ g[/tex]

So, the required mass is 108.33 grams.

Answer:

7.89 m/s

Explanation:

Given that

Width of the river, b1 = 12 m

Width of the river, b2 = 5.8 m

Depth of the river, d1 = 2.7 m

Depth of the river, d2 = 0.85 m

Speed of the river, v1 = 1.2 m/s

Speed of the river, v2 = ?

Area of the river before the rapid, a1 = 12 * 2.7 = 32.4 m²

Area of the river after the rapid, a2 = 5.8 * 0.85 = 4.93 m²

To solve this question, we use a relation between the speed of the river and the volume of the river. We say,

Area1 * velocity1 = Area2 * velocity2, and when we substitute the values for each other we have

32.4 * 1.2 = 4.93 * v2

38.88 = 4.93v2

v2 = 38.88 / 4.93

v2 = 7.89 m/s

Therefore, the speed of the river after the rapid is 7.89 m/s

Answer: 9.3m/s

Explanation:

Your question isn't complete but let me help out:

A 0.060 kg ball hits the ground with a speed of –32 m/s. The ball is in contact with the ground for 45 milliseconds and the ground exerts a +55 N force on the ball. What is the magnitude of the velocity after it hits the ground?

We would use Newton's law of motion to solve this which goes thus:

F = ma

f = m(v-u)/t

Cross multiply

ft = m(v-u)

where,

f = 55

t = 45/1000 = 0.045

m = 0.0060

u = -32

v = Unknown

Therefore,

55 × 45/1000 = 0.060(v - -32)

55 × 0.045 = 0.060(v + 32)

2.475 = 0.06(v + 32)

2.475 = 0.06v + 1.92

0.06v = 2.475 - 1.92

0.06v = 0.555

v = 0.555/0.06

v = 9.25m/s

v = 9.3m/s Approximately

Answer:

A.9.3 m/s

Explanation:

Answer:

The thermal energy is carried by electromagnetic waves

Explanation:

There are three types of transfer of heat (thermal energy):

- Conduction: conduction occurs when two objects/two substances are in contact with each other. The heat is transferred from the hotter object to the colder object by the collisions between the molecules of the two mediums.

- Convection: convection occurs when a fluid is heated by an external source of heat. The part of the fluid closer to the heat source gets warmer, therefore it becomes less dense and it rises, and it is replaced by the colder part of the fluid, which is colder. Then, this part of fluid is heated as well, so it gets warmer, it rises, etc.. in a cycle.

- Radiation: radiation occurs when thermal energy is carried by electromagnetic waves. Since electromagnetic waves do not need a medium to propagate, this is the only method of heat transfer that can occur through a vacuum (so, in space as well).

Indeed, the Sun emits a lot of electromagnetic radiation, which travels through space and eventually reaches the Earth, heating it.

Explanation:

a= 1156× 6.13= 7086.28

Explanation:

a = m× m/ s^2

Answer:

You and your buddy are scuba diving and notice that air bubbles triple in volume as they rise to the surface from where you are in the ocean. Ignoring any temperature changes, how far below the surface of the water (in m) are you when these bubbles are released? The ocean has a density of 1034 kg/m3

Answer: 44.76 kg

Explanation: There are two options for formulas to use here.

0=(m1)(V1f)+(m2)(V2f)

Or

(m1)(V1f) = —(m2)(V2f)

Both formulas should give you an answer of 44.763514, which can be rounded to the specifications of whatever your curriculum or teacher wants. Most likely 44.76.

Blessings to all of you in the Name of Jesus Christ our Savior!

Answer:

The weight of an astronaut plus his space suit on the Earth is 1,931.69 N.

Explanation:

Newton's second law, called the fundamental law or fundamental principle of dynamics, states that a body accelerates if a force is applied to it. This law indicates that the net force applied on a body is proportional to the acceleration that the body acquires. The constant of proportionality is the mass of the body, so Newton's second law is expressed in the following formula:

F = m*a

Where:

The weight of an astronaut plus his space suit on the Moon is only 319 N. Then, being:

you get:

319 N= m* 1.62 m/s²

Solving:

[tex]m=\frac{319 N}{1.62 \frac{m}{s^{2} } }[/tex]

m=196.91 kg

The mass is an invariable quantity, regardless of the planet in which the astronaut plus his space suit on the Moon is, then you have:

replacing in the definition of force:

Weight= 196.91 kg* 9.81 m/s²

Weight= 1,931.69 N

The weight of an astronaut plus his space suit on the Earth is 1,931.69 N.

Answer:

Inclined Plane

Explanation:

Answer:

Explanation:

the lowest points of a transverse wave are called the troughs what is the wavelength of a wave traveling through a rope if the distance from one crest to the next is 1 meter a. 2 m

4. Low points are called troughs

5. Medium: substance through which a wave can travel

Answer:

Explanation:

This image is the example of Newton's first law of motion because:

As per Newton's first law, football will remain in the state of rest until a player applies an external force by kicking the ball.

And the ball will keep on moving until unless the net of a goal post exerts the external force to stop the ball.

Answer:The answer is when a metal plate is pressed against a fast spinning piece of steel hard enough to stop it. i know this because I just took a test and got this question and got it write

Explanation:

[tex]\sf{\underline{\underline{\qquad \clubsuit \: Given :\clubsuit\qquad}}} \\ [/tex]

[tex]\sf{\underline{\underline{\qquad \clubsuit \: To \:Find :\clubsuit\qquad}}} \\ [/tex]

[tex]\sf{\underline{\underline{\qquad \clubsuit \: Solution :\clubsuit\qquad}}} \\ [/tex]

[tex]:\implies\sf Pressure = \dfrac{Force}{Area} \\ \\ \\ [/tex]

[tex]:\implies\sf Pressure = \dfrac{50}{5} \\ \\ \\ [/tex]

[tex]:\implies \underline{ \boxed{\sf Pressure = 10 \:pascal }}\\ \\ \\ [/tex]

[tex]\therefore{\underline{\textsf{The pressure exerted by the fluid is \textbf{10 pascal}}}}. \\ [/tex]

They could determine it by counting their total amount of miles mark went by the directions he went to walk those miles.

4.80m/s

(d) Since v y >0 when the ball hits the wall, it has not reached the highest point yet.

Answer:

C -) The friction between an object and air.

Explanation:

The frictional force is the force that exists between two surfaces in contact, which is opposed to the movement.

That is, this type of force exists as long as there is physical contact between surfaces.

While the other types of force always act at a separation distance between bodies.

Answer:

A longitudinal wave is a wave where the displacement of the medium is in the same direction than the propagation of the wave.

This means that as a P wave travels through the Earth, the relative motion between the p wave and the particles is near zero, as the motion of the particles is parallel to the motion of the wave.

An example of this would be the waves generated when you throw a rock in water, you can see how the water particles move along the waves in the water.

The relative motion between the p wave and the particles is almost negligible.

Learn more:

https://brainly.com/question/26095273

Answer: 6.022×10²³ molecules of CH4 which consists of 1 mole of C atoms and 4 moles of H atoms.

Answer:

0.255 meters

Explanation:

cause formula to calculate work done against gravity is mgh where m refers mass g refers acceleration due to gravity and h refers height

no cap bro bro i thinks its poop Explanation: