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3 years ago

If a car passes a pedestrian, a change in pitch is __________.

2 answers:

6 0

Given two questions:

<span>1) If a car passes a pedestrian, a change in pitch is ______________.
The answer is the change in pitch is perceived by the pedestrian since he is the one in a relatively constant position compared to the car passing.

2) </span><span>In the Doppler Effect lab, which statement best describes what you demonstrated about speed and pitch?

The answer is 'speed and direction affect pitch'.</span>

marusya05 [52]3 years ago

4 0

The correct answers are as follows:

1. If a car passes a pedestrian, a change in pitch is PERCEIVED BY THE PEDESTRIAN.

The pitch of a sound refers to the quality of sound that makes it to be rated as a low or a high sound. Pitch varies with distance, that is, as one moves closer to a source of sound, the sound pitch increases and as one move away from the source of a sound, the pitch of the sound decreases. In the question given above, a change in pitch of the car sound will be perceived by the pedestrian, this is because, his position is constant relevant to that of the passing car. As the car moves away the sound pitch will decreases.

2. The correct answer is this: SPEED AND DIRECTION AFFECT PITCH.

Doppler effects refers to the increase or decrease in the pitch of a sound as one move towards or away from a sound. This change in sound is due to changes in the frequency of the sound. Speed and direction are two factors that affect the pitch of a sound.

You might be interested in

If the melted lead got hot enough to vaporize, how much energy would it have taken to vaporize 21

arsen [322]

Answer:

18 KJ

Explanation:

Data Given:

mass of Lead (m) = 21 g

Heat taken for vaporization (Q) = ?

Solution:

This problem is related to phase change and latent heat of vaporization.

Latent heat of vaporization is the amount of heat taken to convert one mole of substance at its boiling point to its vapor.

So, Latent heat of vaporization of lead has a constant value

Latent heat of vaporization of lead = 177.7 KJ/mol

Formula used

Q = m x Lv. . . . . (1)

where

Lv = specific latent heat of vaporization

here the value for latent heat of vaporization is for mole so instead of mass we will use moles in formula.

So,

Q = no. of mol x Lv. . . . . (2)

first find no. of moles for 21 g of lead

no. of moles = mass in grams / molar mass . . . . . . (3)

molar mass of lead (Pb) = 207 g/mol

put values in equation 3

no. of moles = 21g / 207 g/mol

no. of moles = 0.101 mol

so,

number of moles of lead (Pb) = 0.101 mol

Put values in the eq.2

Q = 0.101 mol x 177.7 KJ/mol

Q = 18 kJ

So, 18KJ of heat is taken to vaporize 21 g of lead (Pb)

5 0

3 years ago

A new garage door opener app is introduced to the market, claming it can close your garage door from a farther distance than a t

Semmy [17]

Answer:

I would answer but not enough information

8 0

3 years ago

How does your pattern of breathing change when you exercise and then rest ?

Paladinen [302]

Your pattern of breathing increases, making it faster than usual, when you're exercising because you're pushing your body to work harder and speeding up your heart rate making you tired.

When you're resting your breathing pattern should be steady and normal since you aren't doing anything that requires lots of body work or something that would make you out of breath.

Hope this helps,

Davinia.

7 0

3 years ago

Which equation represents a transuranium

Maksim231197 [3]

Answer:

1) Since you have not provided the equations to select the right one, I am going to explain you the relevant facts that are used to solve this question.

2) The transuranium elements are the chemiical elements with atomic number greater than that of the uranium.

The atomic number of uranium is 92. So, the transuranium elements are the elements with atomic number 93 or greater.

This are some of the transuranium elements:

Neptunio - 93

Plutonium - 94

Americium - 95

Curium - 96

Berkelium - 97

Californium - 98

Einstenium - 99

And so all the known elements (the last one is the 118).

3) In a nuclear reaction the total mass number ( shown as superscript to the left of the symbol) and total atomic number (shown as subscript to the left of the symbol) are conserved.

4) Beta decay is the release of a beta particle, which is an electron (considered massles and with charge - 1). So, the beta decay is represented with the symbol:

β, which means 0 mass and charge - 1.

-1

5) This is, then, an example of a β decay equation for one transuranium element:

239 239 0

Np → Pu + β

93 94 -1

As you see 239 = 239 + 0 and 93 = 94 - 1, showing that the total mass number ( shown as superscript to the left of the symbol) and the total atomic number (shown as subscript to the left of the symbol) are conserved.

Explanation:

3 0

3 years ago

n the reaction Mg (s) + 2HCl (aq) H2 (g) + MgCl2 (aq), how many moles of hydrogen gas will be produced from 75.0 milliliters of

Xelga [282]

0.075 L * 1.0 M = 0.075 mol HCl
H2 is half of HCl by the coefficients divide 0.075 by 2 and get 0.0375 mol H2 gas

8 0

3 years ago