The photons of different light waves:

Answer:

The resultant of two vectors:

P

  and    

Q

​  

 is given by  

R=  

P  

2

+Q  

2

+2PQcosθ

​  

where, P and Q are magnitudes of two vectors and θ is the angle between two vectors.

Here θ=?  P=8N  Q=15N  R=17N

Therefore,

17=  

8  

2

+15  

2

+2×8×15cosθ

​  

289=64+225+240cosθ

289=289+240cosθ

289−289=240cosθ

cosθ=0

cosθ=cos90

θ=90  

0

Explanation:

Answer:

The nodes and anti nodes would reverse roles.

Explanation:

I believe it has to do with the path differences. If waves are in phase, then the path differences are such that the waves reach the screen with crests superimposing crests and troughs superimposing troughs. This happens when the periods of each wave are equal or the paths themselves differ by a whole number multiple of the wavelength (λ, 2λ, 3λ, ...).

Now make these waves out of phase. Then half of the waves will travel half a wavelength farther than the rest. So the path difference will be 0.5λ, 1.5λ, 2.5λ, ....

Answer:

linear motion

Explanation:

the birds in the sky show oscillatory motion when they flap their wings

Answer:

1.6 kJ

Explanation:

0.40 (4 kJ) = 1.6 kJ

Answer:

Explanation:

When a lightning bolt travels from the cloud to the ground it actually opens up a little hole in the air, called a channel. Once then light is gone the air collapses back in and creates a sound wave that we hear as thunder. The reason we see lightning before we hear thunder is because light travels faster than sound!

Answer:

light travels faster than sound

Explanation:

Answer:

1.) 1620 km/h^2

2.) 2.7 km

Explanation:

1.) Given that the car start from rest. The initial velocity U will be equal to zero. That is,

U = 0.

Final velocity V = 54 km/h

Time t = 2 minute = 2/60 = 1/30 hour

Acceleration a will be change in velocity per time taken. That is,

a = ( V - U )/ t

Substitute V, U and t into the formula

a = 54 ÷ 1/30

a = 54 × 30 = 1620 km/h ^2

2.) Distance travelled S by the car during the time can be calculated by using the 2nd equation of motion.

S = Ut + 1/2at^2

Substitute all the parameters into the formula

S = 54 × 1/30 + 1/2 × 1620 × (1/30)^2

S = 54/30 + 810 × 1/900

S = 54/30 + 810/900

S = (1620+810)/900

S = 2430/900

S = 2.7 km.

Therefore, distance travelled by the car during this time is 2.7 km

Answer:

example of adaptation in mangrove

Mangroves are salt-tolerant trees, also called halophytes, and are adapted to life in harsh coastal conditions. They contain a complex salt filtration system and complex root system to cope with salt water immersion and wave action. They are adapted to the low oxygen conditions of waterlogged mud.

adaptation of rainforest

Many animals have adapted to the unique conditions of the tropical rainforests.

hope this can help you

The correct answer is D. Amount of time and area of physical contact between the substances.

Explanation:

Heat transfer refers to the flow of thermal energy or heat between two or more objects. This process involves multiple factors and implies heat from the hottest object goes to the coldest one until there is an equilibrium. To begin, heat transfer depends on the amount of thermal energy in the objects because objects must have a different amount of thermal energy for heat to flow.

Besides this, the amount of energy that flows depends on the time and the contact between the substances of objects. Indeed, objects need to be in contact or close to each other for heat to transfer, and the time needs to be enough for the process to occur. For example, if you place a pot over the fire just for a few seconds it is likely the heat transferred is minimal, which does not occur if you leave the pot more time. At the same time if the pot is in close contact with fire more heat will be transferred.-

Answer:

the answer is D on edginuity.

Explanation:

Answer:

Explanation:

Answer:

electrical energy is energy derived from electric potential energy or kinetic energy. when loosely electrical energy refers to energy that has been converted from electric potential energy

Answer:

electrical energy is energy derived from electric potential energy or kinetic energy. when loosely electrical energy refers to energy that has been converted from electric potential energy

Explanation:

Answer:

circular motion

Explanation:

As a motorcycle takes a sharp turn, the type of motion that occurs is called circular motion.

Circular motion is a movement of an object along a circular path. As this motorcycle makes the sharp turn, it is acted upon by a centripetal force which directs the motorcycle towards the center.

Therefore, circular motion is the correct answer to the question.

Answer:

Circular Motion

Answer:

The correct options are;

1) The chemical composition of our solar system matches the chemical composition of the Milky Way

2) Nearly all atoms of elements heavier than helium were produced through nuclear fusion in stellar interiors and through reactions that occur during explosions that massive stars undergo at the ends of their lives or during mergers of stellar remnants called neutron stars

3) Some of the oldest galaxies are about 13.2 billion years old

4) Nucleosynthesis is a process through which the atoms of various elements are produced

5) You re mainly made of hydrogen

Explanation:

1) There are dependencies between chemical composition of stars and planets and the same distribution of chemicals we have in our Solar system have been observed to be present in varying resemblance through out the Milky Way

2) The formation of heavier elements are believed to have been formed by astrophysical fusion processes

3) The oldest known object (and hence the galaxy where the star resides), is from a distant star known as GRB 090423 which is about 13 billion years old

4) New atomic nuclear are created by the process of protons and neutrons by the process of nucleosynthesis

5) 62%of the atoms in the body are hydrogen atoms.

Answer:

42.11 years old

Explanation:

Given that:

In 2000, a 20-year-old astronaut left Earth to explore the galaxy; her spaceship travels at 2.5 x 10^8 m/s. She returns in 2040

To find her age we use:

[tex]\Delta t_m=\frac{\Delta t_s}{\sqrt{1-\frac{v^2}{c^2} } }\\[/tex]

Δtm is  time interval for the observer stationary relative to the sequence of

events = 2040 - 2000 = 40 years

Δts is is the time interval for an observer moving with a speed v relative to the  sequence of event

v = velocity = 2.5 x 10^8 m/s

c = speed of light = 3 x 10^8 m/s

[tex]\Delta t_s=\Delta t_m}{\sqrt{1-\frac{v^2}{c^2} } }\\\Delta t_s=40\sqrt{1-\frac{(2.5*10^8)^2}{(3*10^8)^2}}\\\Delta t_s=22.11\ yr[/tex]

Here age in 2000 is 20 year, therefore when she appear she would be 20 year + 22.11 year = 42.11 years old

Explanation:

horizontal velocity = 30 x Cos45 = 19.48m/s

to find horizontal displacement

vertical velocity = 30 x Cos45 = 22.81m/s

vertical displacement = vertical velocity x time

vertical displacement = 22.81 x 2 = 45.62m

Answer:

Displacement after two seconds

= <Dx,Dy> = <42.426, 1.593> m to three decimal places

Explanation:

Given:

arrow shot at 30m/s and 45 degrees with horizontal.

Hit bull's eye after 2 seconds.

Find horizontal and vertical displacements.

Vx = 30cos(30) m/seconds  constant  velocity

therefore

Dx = Vx*t = 30cos(30) m/s *  2 s = 60 cos (45) = 42.426 m

Vy = 30 sin(45) m/s  

Dy = Vy*t + a(t^2) /2  

= 30*sin(45) -9.81(2^2)/2        (g is accelerating downwards, so negative)

= 1.593 m

The net displacement after 2 seconds is

D = <Dx,Dy> = <42.426, 1.593> m to three decimal places

Answer: I did these exercises outdoors. The weather was hot and humid, so I drank about two cups of water during the workout. I also drank a cup of water about an hour before I started. Yes, the weather most definitely affected how much I drank.

Explanation: Edmentum

Answer:William Herschel found the seventh planet now known as uranus

<!> Brainliest is appreciated! <!>

Explanation:

Answer:

William Herschel

Explanation:

Answer:

C

Explanation:

[tex]\dfrac{50km}{h}\cdot 0.5h= \\\\\\50km\cdot 0.5=25km[/tex]

Therefore, the correct answer is choice C. Hope this helps!

The correct answer is C.

It is C because .5 h is equal to 30 minutes. So half of 50 km is 25 km(Divided by 2)

Answer:

44.1 W

Explanation:

Power = Voltage x current

(P = VI)

P = 12.6 x 3.5

P = 44.1 W

Answer:

A opção A está correta.

O sistema formado pela garrafa térmica e a água perde 400 cal de calor para o meio ambiente.

Option A is correct.

The system formed by the thermos and the water loses 400 cal of heat to the environment.

Explanation:

Quando a temperatura de um sistema reduz, fica claro que o sistema perdeu calor ou energia térmica. Como a temperatura é um dos indicadores mais claros disso, esta conclusão é hermética e correta.

Mas, para saber a quantidade de calor perdida para o meio ambiente, agora fazemos alguns cálculos de energia térmica.

Transferência de calor de ou para o sistema de água e garrafa térmica = c × ΔT

c = capacidade térmica do sistema de água e garrafa térmica = 80 cal /°C

ΔT = Alteração da temperatura do sistema de água e garrafa térmica = (temperatura final) - (temperatura inicial) = 55 - 60 = -5°C

Calor transferido = 80 × -5 = -400 cal.

O sinal de menos mostra que o calor é transferido para fora do sistema, ou seja, o calor é perdido no sistema.

Espero que isto ajude!!!

English Translation

The thermos (also known as "Dewar vase") is an extremely useful device to conserve bodies (essentially liquid) at high temperatures, minimizing energy exchanges with the environment, which is generally colder. A thermos contains water at 60 o C. The thermos + water set has a thermal capacity of C = 80 cal / o C. The system is placed on a table and, after a considerable period of time, its temperature decreases to 55 o C. In this case, it is concluded that the system formed by the thermos and the water inside:

a) lost 400 cal. B) gained 404cal. C) lost 4 850 cal. D) gained 4 850 cal. E) did not exchange heat with the external environment.

Solution

When a system's temperature reduces, it is clear to conclude that the system has lost heat or thermal energy. Since temperature is one of clearest indicators of this, this conclusion is airtight and correct.

But, to know the amount of heat lost to the environment, we now do some thermal energy calculations.

Heat transferrred from or to the water and thermos system = c × ΔT

c = heat capacity of the water and thermos system = 80 cal/°C

ΔT = Change in temperature of the water and thermos system = (final temperature) - (initial temperature)

= 55 - 60 = -5°C

Heat transferred = 80 × -5 = -400 cal.

The minus sign shows that the heat is transferred out of the system, that is, the heat is lost from the system.

Hope this Helps!!!

Answer:

If a body covers equal displacement in equal interval of time,however small may be the body is said to have uniform velocity. If a body covers in equal displacement in equal interval of time is called variable velocity.

Answer:

(a)     T = 4.09*10^-8 s

(b)     r = 0.19m

Explanation:

(a) In order to determine the rotational period of the protons, you first calculate the angular speed of the proton. You use the following formula for the radius of the trajectory described by the electron in a region with a constant magnetic field:

[tex]r=\frac{mv}{qB}[/tex]               (1)

m: mass of the proton = 1.67*10^-27 kg

q: charge of the proton = 1.6*10⁻19C

B: magnitude of the magnetic field = 1.6T

v: speed of the proton = 0.1c = 0.1(3*10^8m/s) = 3*10^7m/s

The angular speed of the proton is v/r, then, you solve for w in the equation (1) and replace the values of the parameters:

[tex]\omega=\frac{v}{r}=\frac{qB}{m}\\\\\omega=\frac{(1.6*10^{-19}C)(1.6T)}{1.67*10^{-27}kg}=1.53*10^8\frac{rad}{s}[/tex]

The rotational period T is:

[tex]T=\frac{2\pi}{1.53*10^8rad/s}=4.09*10^{-8}s[/tex]

(b) The radius of the protons' orbit is calculated by using the equation (1):

[tex]r=\frac{(1.67*10^{-27}kg)(3*10^7m/s)}{(1.6*10^{-19}C)(1.6T)}\\\\r=0.19m[/tex]

The radius of the protons' orbit is 0.19m

Answer:

Explanation:

I personally believe one key disadvantages is the cost of maintaining the equipment unlike the gym where you have to subscribe for the month or the year and forget about anything, owning the gym equipment comes with the extra cost and responsibilities of maintenance to the owners.

Answer:

C

Explanation:

Edge 2020

Answer:

1.- para cubrir la superficie lateral 4.32 metros²

2.- Area de la base  2.15 metros²

3.- Volumen 1 m³

4.- Area total 6.47 metros²

Explanation:

El área lateral sera calcular el area de seis triangulos iguales cuya base es

0.80 de base x 6 lados = 4.80 metros perimetro de la base

4.80 perimetro de base x 1.80 arista lateral / 2 = 4.32m2

Area de la base:

Perímetro x Apotema / 2

Siendo la Apotema la altura de los triangulos que componen un hexagono calculada utilizando el teorema de pitágoras:

[tex]\sqrt{0.8^2 + (0.8/2)^2} = Apotema[/tex]

Apotema = 0.894427191

Area: 4.80 x 0.894427191 / 2 = 2.146625258

sumando el area de la base mas el area lateral se obtiene el area total

2.15 + 4.32 = 6.47 metros

Volumen de la pirámide:

Area de la Base x Altura / 3

2.15 x 1.40 / 3 = 1.00333 m3

Answer:

-Women are now allowed to participate in the Olympics unlike before when it was only men allowed.

-Modern Olympic Games include many more events. There are more than 20 different sports and almost 300 events in the modern games, while the first Olympics only had running.

-The Olympics are held every two years. While the ancient Olympics were originally held every four years.

-Athletes from countries around the world participate in the modern Olympics unlike in the ancient Olympics where only athletes from ancient Greece competed.

Explanation:

Edmentum Plato answer (i already reworded most of it so you don't have to) <33

Answer:

Answer:

white

Explanation:

white is less absorbent then black

Answer:

a) [tex] \Delta U = 7.5 kJ [/tex]

b) [tex]T_{f} = 900 K [/tex]

Explanation:

a) To find the change in its internal energy (U) we need to use the following equation:

[tex] \Delta U = W + Q [/tex]

Where:

W: is the work done on the system

Q: is the energy transferred into the system by heat = 12.5 kJ

Since we have an isobaric expansion, the work is:

[tex] W = - P\Delta V = - P(V_{f} - V_{i}) [/tex]

Where:

[tex]V_{f}[/tex]: is the final volume = 3.00 m³

[tex]V_{i}[/tex]: is the initial volume = 1.00 m³

P: is the pressure = 2.50 kPa

[tex] W = -P(V_{f} - V_{i}) = -2.5 \cdot 10^{3} Pa(3.00 m^{3} - 1.00 m^{3}) = -5.00 \cdot 10^{3} J [/tex]

Now, we can find the change in its internal energy:

[tex] \Delta U = W + Q = -5.00 \cdot 10^{3} J + 12.5 \cdot 10^{3} J = 7.5 \cdot 10^{3} J [/tex]

b) The final temperature can be found as follows:

[tex] \frac{V_{i}}{V_{f}} = \frac{T_{i}}{T_{f}} [/tex]

[tex] T_{f} = \frac{T_{i}*V_{f}}{V_{i}} = \frac{300 K*3.00 m^{3}}{1.00 m^{3}} = 900 K [/tex]

Hence, the final temperature is 900 K.

I hope it helps you!

Answer:

a) 588.235 ohm ( all the 3 resistors are in parallel )

b) 10 A

c) Current flowing -

in 20 ohm resistor = 6.25 A

in 100 ohm resistor = 1.25 A

in 50 ohm resistor = 2.5 A

d) Voltage drop across all the resistor = 125 V

(As all the resistors are in parallel all the resistors will have the same voltage drop )

e) Power dissipated -

in 20 ohm resistor = 781.25 W

in 100 ohm resistor = 156.25 W

in 50 ohm resistor = 312.5 W

(Power = Current × Potential Difference)

Answer:

Net force will be 36,480 N

Explanation:

As force equation is F=ma, here F =force in newton, m, mass in kg, a =acceleration in metre per second.

so F = 30400 kg * 1.20 metre per second

which will be F= 36480 Newtons

F=36480 N

Answer:

D. 1.2 × 102 newtons

Explanation:

The computation of the normal force acting on the bag is shown below:

It could find out by applying the following formula

Normal force =  Force ÷  coefficient of kinetic friction

where,

Force is 27 newtons

And, the  coefficient of kinetic friction is 0.23

Now placing these values to the above formula

So, the normal force is

= 27 newtons ÷ 0.23

= 117.39 N

Therefore the correct option is D.