PHYSICS COLLEGE

A 4,667 kHz AM radio station broadcasts with a power of 84 kW. How many photons does the transmitting antenna emit each second.

Answers

Answer 1

Answer:

Answer:

Explanation:

Frequency( ν ) 4667 x 10³ Hz = 4.667 x 10⁶ Hz

Energy of one photon = hν [ h is plank's constant ]

= 6.6 x 10⁻³⁴ x 4.667 x 10⁶ = 30.8 x 10⁻²⁸ J

Power = 84 x 10³ J/s

No of photons emitted = Power / energy of one photon

= 84 x 10³ / 30.8 x 10⁻²⁸ =2.727 x 10³¹ per second .

Related Questions

A Porsche sports car can accelerate at 8.8 m/s^2. Determine its acceleration in km/h^2.
The left ventricle of a resting adult's heart pumps blood at a flow rate of 85.0 cm3/s, increasing its pressure by 110 mm Hg, its velocity from zero to 25.0 cm/s, and its height by 5.00 cm. (All numbers are averaged over the entire heartbeat.) Calculate the total power output (in W) of the left ventricle. Note that most of the power is used to increase blood pressure.
Twopucksofequalmasscollideonafrictionlesssurface,asillustratedinthefigure.Immediatelyafterthe collision, the speed of the black puck is 1.5 m/s. What is the speed of the white puck immediately after the collision?
Calculate the de Broglie wavelength of an electron and a one-ton car, both moving with speed of 100 km/hour. Based on your calculation could you predict which will behave like a "quantum particle" and why. Please explain each step in words and detail.
Convert this measurement664.2 km=____cm

A baseball leaves the bat with a speed of 40 m/s at an angle of 35 degrees. A 12m tall fence is placed 130 m from the point the ball was struck. Assuming the batter hit the ball 1m above ground level, does the ball go over the fence? If not, how does the ball hit the fence? If yes, how far beyond the fence does the ball land?

Answers

Answer:

The ball land at 3.00 m.

Explanation:

Given that,

Speed = 40 m/s

Angle = 35°

Height h = 1 m

Height of fence h'= 12 m

We need to calculate the horizontal velocity

Using formula of horizontal velocity

$V_(x)=V_(i)\cos\theta$

$V_(x)=40*\cos35$

$V_(x)=32.76\ m/s$

We need to calculate the time

Using formula of time

$t = (d)/(v)$

$t=(130)/(32.76)$

$t=3.96\ sec$

We need to calculate the vertical velocity

$v_(y)=v_(y)\sin\theta$

$v_(y)=40*\sin35$

$v_(y)=22.94\ m/s$

We need to calculate the vertical position

Using formula of distance

$y(t)=y_(0)+V_(i)t+(1)/(2)gt^2$

Put the value into the formula

$y(3.96)=1+22.94*3.96+(1)/(2)*(-9.8)*(3.96)^2$

$y(3.96)=15.00\ m$

We need to calculate the distance

$s = y-h'$

$s=15.00-12$

$s=3.00\ m$

Hence, The ball land at 3.00 m.

in the demolition of an old building,a 1,300 kg wrenching ball hits the building at 1.07m/s^2.Calculate the amount of force at which the wrecking ball strikes the building

Answers

Answer:

1391 N

Explanation:

The force acting on an object given it's mass and acceleration can be found by using the formula

force = mass × acceleration

From the question we have

force = 1300 × 1.07

We have the final answer as

1391 N

Hope this helps you

24-gauge copper wire has a diameter of 0.51 mm. The speaker is located exactly 4.27 m away from the amplifier. What is the minimum resistance of the connecting speaker wire at 20°C? Hint: How many wires are required to connect a speaker!Compare the resistance of the wire to the resistance of the speaker (Rsp = 8 capital omega)

Answers

Answer:

R = 8.94 10⁻² Ω/m, R_sp / R_total = 44.8

Explanation:

The resistance of a metal cable is

R = ρ L / A

The area of a circle is

A = π R²

The resistivity of copper is

ρ = 1.71 10⁻⁸ ohm / m

Let's calculate

R = 1.71 10⁻⁸ 4.27 / (π (0.51 10⁻³)²)

R = 8.94 10⁻² Ω/m

Each bugle needs two wire, phase and ground

The total wire resistance is

R_total = 2 R

R_total = 17.87 10⁻² Ω

Let's look for the relationship between the resistance of the bugle and the wire

R_sp / R_total = 8 / 17.87 10⁻²

R_sp / R_total = 44.8

Final answer:

The resistance of the speaker wire can be calculated using the formula for the resistance of a wire, taking into account the resistivity of copper, the length and thickness of the wire, and whether a single or pair of wires is used.

Explanation:

The question is asking you to find the minimum resistance of a copper wire given its diameter and length, plus the resistance of the speaker it's connected to. Resistance of a wire is calculated using the formula R=ρL/A, where R is the resistance, ρ (rho) is the resistivity of the material (in this case, copper), L is the length of the wire, and A is the cross-sectional area of the wire.

First, you need to find the area of the 0.51 mm diameter wire. The area (A) of a wire is given by the formula π(d/2)^2 where d is the diameter of the wire. After calculating the area, use the formula R=ρL/A to calculate the resistance. For copper wire at 20°C, ρ is approximately 1.68 × 10^-8 Ω·m. Substituting these values into the formula will give you the resistance of the wire in ohms.

Note: you may need to consider whether you have just a single wire or a pair, since two wires are typically required to connect a speaker. If a pair is used, each wire will carry half the current, which affects the total resistance.

Learn more about Electric Resistance here:

brainly.com/question/31668005

#SPJ12

On a trip, you notice that a 3.50-kg bag of ice lasts an average of one day in your cooler. What is the average power in watts entering the ice if it starts at 0ºC and completely melts to 0ºC water in exactly one day 1 watt = 1 joule/second (1 W = 1 J/s) ?

Answers

Answer:

$P=13.5 W$

Explanation:

In this case, power is the rate of transferring heat per unit time:

$P=(Q)/(\Delta t)(1)$

The heat is given by the formula of the latent heat of fusion, since the ice is melting.

$Q=mL_f(2)$

Here m is the ice's mass and $L_f$ is the heat of fusion of ice. Recall that one day has 86400 seconds. Replacing (2) in (1) and solving:

$P=(mL_f)/(\Delta t)\nP=(3.5kg(334*10^3(J)/(kg)))/(86400s)\nP=13.5 W$

A 750-kg automobile is moving at 26.2 m/s at a height of 5.00 m above the bottom of a hill when it runs out of gasoline. The car coasts down the hill and then continues coasting up the other side until it comes to rest. Ignoring frictional forces and air resistance, what is the value of h, the highest position the car reaches above the bottom of the hill?

Answers

To solve this problem it is necessary to apply to the concepts related to energy conservation. For this purpose we will consider potential energy and kinetic energy as the energies linked to the body. The final kinetic energy is null since everything is converted into potential energy, therefore

Potential Energy can be defined as,

$PE = mgh$

Kinetic Energy can be defined as,

$K= (1)/(2) mv^2$

Now for Conservation of Energy,

$KE_i+PE_i = PE_f$

$(1)/(2)mv_i^2+mgh_1 = mgh_2$

$(1)/(2) (750kg) (26.2m/s)^2 + (750)(9.8)(5) = (750)(9.8)h_2$

$h_2 = 40.0224m$

Therefore the highets position the car reaches above the bottom of the hill is 40.02m

A series circuit contains a 20-Ω resistor, a 200-mH inductor, a 10-μF capacitor, and an ac power source. At what frequency should the power source drive the circuit in order to have maximum power transferred from the driving source?

Answers

Answer:

f = 113 Hz

Explanation:

In order to have maximum power transferred from the driving source, as the RMS voltage doesn´t depends on frequency, the current I must be maximum.

This condition is met when the circuit behaves a purely resistive, as the impedance is at a minimum.

Such condition is known as resonance, and it satisfies the following equation:

XL = XC ⇒ ω₀ * L = 1 / ω₀*C, where ω₀, is the angular frequency at resonance.

Solving for ω₀, we have:

ω₀ = 1/√LC = 1/√200*10⁻3 H* 10⁻6F = 707 rad/sec

As we need to find the frequency (in cycles/sec), we need to convert from angular frequency to frequency, as follows:

ω₀ = 2*π*f₀ ⇒ f₀ = ω₀ / 2*π = 707 rad/sec / 2*π rad = 113 Hz

Other Questions

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

An F-35 stealth jet takes off from the aircraft carrier Ronald Reagan. Starting from rest, the jet accelerated with a constant acceleration of 55.3 m/s2 along a straight line on the deck. What is the displacement of the jet when it reaches a speed of 181 m/s?

Three small objects are arranged along a uniform rod of mass m and length L. one of mass m at the left end, one of mass m at thecenter, and one of mass 2m at the right end. How far to the left or right of the rod's center should you place a support so that the rodwith the attached objects will balance there?

Ugoing o pri7.) True or False: "Courtney is traveled 5 miles in 3 hours" is an example ofacceleration.TrueFalse