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3 years ago

PLZ HELP

Physics

1 answer:

Vitek1552 [10]3 years ago

8 0

1st

Cell phones depend on both mechanical and electromagnetic waves to be useful. Which answer below correctly identifies how each wave is used in cell phones?

Correct option

Mechanical waves allow the cell phone to emit a sound when ringing; Electromagnetic waves allow a signal to be picked up when making a call.

(Mechanical waves, made by oscillating a membrane inside the phone are responsible for sound. While electromagnetic waves, such as radio signals, allow us to make phone calls)

2nd

True or False. The Electromagnetic Spectrum can be described in terms of wave energy, frequency, and wavelength.

Correct option

True because the electromagnetic spectrum is ordered based on wave energy, which is described on a wave as wavelength and frequency.

(These are the basic characteristics of an electromagnetic wave, and depending of the frequency, they carry an specific amount of energy.)

You might be interested in

What could serve as ballast for a balloon? Help pls...thx

I am Lyosha [343]

With the advent of the plastic balloon and the beginning of the unmanned ... That would lead to a more sophisticated ballast system that uses fine steel or iron

6 0

3 years ago

Two radio antennas A and B radiate in phase. Antenna B is a distance of 120 m to the right of antenna A. Consider point Q along

LuckyWell [14K]

Answer:

240 m

120 m

Explanation:

d = Path difference = 120 m

For destructive interference

Path difference

$d=\dfrac{\lambda}{2}\\\Rightarrow \lambda=2d\\\Rightarrow \lambda=2\times 120\\\Rightarrow \lambda=240\ m$

The longest wavelength is 240 m

For constructive interference

$d=\lambda\\\Rightarrow 120\ m=\lambda$

The longest wavelength is 120 m

4 0

3 years ago

What type of circuit is illustrated?

Elis [28]

A. Parallel circuit

Short circuits are circuits that is like plugging in a USB into your computer and the other end to your iPhone, so it's not D.

Series circuits can come in all kinds of different shapes, so it's not C.

Open circuits are circuits that are opened, meaning that whenever you turn on the light and it's an open circuit, it won't work cause the two wires are not connected, meaning it's not D.

Parallel circuits are circuits that are in one straight line, just like parallel lines, meaning the answer would be A. (Look at the picture and don't get confused with the other question that's the same question and has the same answers, they both have different pictures, so look at the pictures they give you whenever they ask the question so your getting the right answer)

Hope this helped.

8 0

3 years ago

Read 2 more answers

Two vehicles approach a right angle intersection and then suddenly collide. After the collision, they become entangled. If their

geniusboy [140]

Answer:

a. 11 m/s at 76° with respect to the original direction of the lighter car.

Explanation:

In this exercise, since both cars make a right angle, let's assume that the lighter car only has a horizontal velocity component (vx) and that the heavier one only has a vertical velocity component (vy). The final velocities for both components for the system can be determined as:

$m_{1} v_{x1}+m_{2}v_{x2}=(m_{1}+m_{2})v_{fx}\\m_{1} v_{y1}+m_{2}v_{y2} =(m_{1}+m_{2})v_{fy}$

Assume that the lighter car has a 1kg mass and that the heavier car has a 4 kg mass.

$1*13 + 4*0 = (1+4) v_{fx}\\v_{fx}=\frac{13}{5} =2.6\\1*0 + 4*13 = (1+4) v_{fy}\\v_{fy}=\frac{13*4}{5} =10.4\\$

The magnitude of the final velocity of the wreck can be found as:

$v_{f}^{2}= v_{fx}^{2}+ v_{fy}^{2}\\v_{f}=\sqrt[]{2.6^{2} + 10.4^{2}} \\v_{f}= 10.72$

The final velocity has an intensity of roughly 11 m/s

As for the angle, it can be determined in respect to the lighter car (x axis) as follows:

$\theta = cos^{-1}(\frac{v_{fx} }{v_{f}} )\\\theta = cos^{-1}(\frac{2.6}{10.7} )\\\theta = 76^{o}$

Therefore, the wreck has a velocity with an intensity of 11 m/s at 76° with respect to the original direction of the lighter car.

5 0

3 years ago

Friction is generated when?

valkas [14]

Things are rubbed against each other

8 0

3 years ago