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Alona [7]
3 years ago
9

A police car travels towards a stationary observer at a speed of 15m/s. the siren on the car emits a sound of frequency 250Hz. C

alculate the observer frequency. the speed of sound is 340m/s​
Physics
1 answer:
skelet666 [1.2K]3 years ago
7 0

Observer Frequency = sound frequency x ( speed of sound / speed of sound - speed of car)

= 250 x (340/( 340-15))

= 261.54 Hz

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What is the strength of the electric field in a region where the electric potential is constant?
Roman55 [17]

Answer:

Where the electric potential is constant, the strength of the electric field is zero.

Explanation:

As a test charge moves in a given direction, the rate of change of the electric potential of the charge gives the potential gradient whose negative value is the same as the value of the electric field. In other words, the negative of the slope or gradient of electric potential (V) in a direction, say x, gives the electric field (Eₓ) in that direction. i.e

Eₓ = - dV / dx        ----------(i)

From equation (i) above, if electric potential (V) is constant, then the differential (which is the electric field) gives zero.

<em>Therefore, a constant electric potential means that electric field is zero.</em>

4 0
3 years ago
PLEASE HELP ASAP Which one of the following is a step used for balancing chemical equations?
scZoUnD [109]

Answer:

C. Count the atoms in each substance in the reactants and products.

Explanation:

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In order for a chemical equation to be balanced, the condition which must be met is that the number of atoms in the reactants equals the number of atoms in the products.

This ultimately implies that, the mass and charge of the chemical equation are both balanced properly.

In Chemistry, all chemical equation must follow or be in accordance with the Law of Conservation of Mass, which states that mass can neither be created nor destroyed by either a physical transformation or a chemical reaction but transformed from one form to another in an isolated (closed) system.

One of the step used for balancing chemical equations is to count the atoms in each substance in the reactants and products.

For example;

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The number of atoms in each chemical element are;

For the reactant side:

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For the product side;

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When we balance the chemical equation, we would have;

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3 0
3 years ago
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Kamila [148]

Explanation:

<h3>1.) Regeneration is the natural process of replacing or restoring damaged or missing cells, tissues, organs, and even entire body parts to full function in plants and animals.</h3>

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6 0
3 years ago
Select the correct answer.
kvasek [131]

Answer:

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Explanation:

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4 0
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