A scientist adds different amounts of salt to 5 bottles of water. She then

Suppose you are standing at the exact center of a park surrounded by a circular road. An ambulance drives completely around this

vladimir2022 [97]

Answer: The pitch of the sound does not change.

Explanation: The pitch of sound wave is dependent on the frequency of the sound wave. The frequency of sound wave when their is a relative motion between an observer and a source is given by Doppler effect.

Doppler effect is a mathematical equation that gives the relationship between the observed frequency by an observer from any sound source and the relative motion between the observer and the source.

Mathematically,

f'= (v+v') /(v-vs) * f

Where f' = observed frequency of sound wave

v= speed of sound in air

v'= velocity of observer relative to sound source

vs= velocity of sound source relating to observer

f= frequency of sound produced by source

The observer is at the center, thus the distance between the observer and the source is constant (according to mensuration, the radius is constant for any given circle and since the car is moving along a circular path and the observer is at the center, thus the distance between them is constant), thus making the relative velocity between the observer and the source constant (vs=constant).

Also the frequency of sound wave produce by the source is a constant (f=constant)

The speed of sound in air is also a constant (v=336m/s)

The observer is standing at the center thus he is not moving, hence the relative motion between observer and source is also constant (v'=constant)

Since all parameters are constant, then the observed frequency will be constant too.

4 0

3 years ago

A space shuttle sits on the launch pad for 2.0 minutes, and then goes from rest to 4600 m/s in 8.0 minutes. Treat its motion as

SpyIntel [72]

Answer:

a.) a = 0 ms⁻²

b.) a = 9.58 ms⁻²

c.) a = 7.67 ms⁻²

Explanation:

a.)

Acceleration (a) is defined as the time rate of change of velocity

$a = \frac{v_{2} - v_{1} } {t}$

Given data

Final velocity = v₂ = 0 m/s

Initial velocity = v ₁ = 0 m/s

As the space shuttle remain at rest for the first 2 minutes i.e there is no change in velocity so,

a = 0 ms⁻²

b.)

Given data

As the space shuttle start from rest, So initial velocity is zero

Initial velocity = v₁ = 0 ms⁻¹

Final velocity = v₂ = 4600 ms⁻¹

Time = t = 8 min = 480 s

By the definition of Acceleration (a)

$a = \frac{v_{2} - v_{1} } {t}$

$a = \frac{4600 - 0 } {480}$

a = 9.58 ms⁻²

c.)

Given data

As the space shuttle is at rest for first 2 min then start moving, So initial velocity is zero

Initial velocity = v₁ = 0 ms⁻¹

Final velocity = v₂ = 4600 ms⁻¹

Time = t = 10 min = 600 s

By the definition of Acceleration (a)

$a = \frac{v_{2} - v_{1} } {t}$

$a = \frac{4600 - 0 } {600}$

a = 7.67 ms⁻²

8 0

3 years ago

When a person speaks, a sound intensity is generated that is 600 times greater than when the person whispers. What is the differ

Charra [1.4K]

Answer:

Originally : Level = log I / I0

Currently: Level = 10 log I / I0

Level = 10 log 600 = 10 * 2.78 = 27.8

Note the term 1 bel = 10 decibels

5 0

2 years ago

In a series RLC resonance circuit, the resonance frequency f0 = 700 kHz. The resistor R = 10 Ohm. The specified bandwidth (BW) s

sladkih [1.3K]

Answer:

quality factor (Q) = 69.99

inductor = 1.591 x 10⁻⁴ H

capacitor = 3.248 x 10⁻¹⁰ F

Explanation:

Given;

resonance frequency (F₀) = 700 kHz

resistor, R = 10 Ohm

bandwidth (BW) = 10 kHz

bandwidth (BW) $= \frac{R}{2\pi L}$

$BW = \frac{R}{2\pi L}$

make L (inductor) the subject of the formula

$L = \frac{R}{2\pi *BW} = \frac{10}{2\pi *10,000} =1.591 *10^{-4} \ H = \ 0.1591\ mH$

$F_o =\frac{1}{2\pi\sqrt{LC} } \\\\\sqrt{LC} = \frac{1}{2\pi F_o} \\\\LC = \frac{1}{4\pi ^2F_o^2}= \frac{1}{4\pi ^2(700,000)^2} = 5.168*10^{-14}$

make C (capacitor) the subject of the formula

$C = \frac{5.168*10^{-14}}{1.591*10^{-4}} = 3.248*10^{-10} \ F = \ 3.248*10^{-4} \ \mu F$

quality factor (Q) $= \frac{1}{R} \sqrt{\frac{L}{C}} \ = \frac{1}{10} \sqrt{\frac{1.591*10^{-4}}{3.248*10^{-10}}}=69.99$

quality factor (Q) = 69.99

5 0

3 years ago

Compare how magnetic forces act through non-magnetic materials and<br>magnetic materials:

gavmur [86]

<h2>Compare how magnetic forces act through non-magnetic materials and </h2><h2>magnetic materials:</h2>

Explanation:

Magnet

• Magnet :- is an object which attracts pieces of iron, steel etc towards itself.

Some facts about magnets:-

• When magnet is freely suspended it always align towards north-south direction

• Like poles always repel & opp. poles attract each other.

• Magnet always exist as dipole

• Two poles can never be separated : if we try to cut it then still both the poles will exist even ina small piece of magnet .it automatically develops the lost polarity

Magnet always develop certain area around it where its effect can be felt ie. magnetic field.

MAGNETIC Field

is studied by drawing imaginary lines called magnetic lines of forces.

Characteristics.

• They always originate from North pole & terminate at South pole. This shows that if north pole was free is move it would have mvre towards south pole.

•Place where they are closer indicate strong M. field i.e. at poles.

•Mag. Field lines gives the direction of magnetic force.

•Two magnetic lines will never intersect each other as they give direction of force & force can’t have 2 direction at a time.

M Field lines are closed continuous curves.

This is what that happens in magnetic materials .

Non magnetic materials

Magnetic forces 'act through' non-magnetic materials
These magnetic materials can be used as a shield around a magnet.
The domain theory of magnetism tries to explain why metals get magnetised
. The magnetic elements have little molecular magnets inside them.
Magnets attract only the magnetic materials

Types of magnetic materials

Soft magnetic materials (e.g. iron) have domains that easily move into line when the metal is placed in a magnetic field but as soon as the field is removed the domains take on a random pattern again. It returns to being unmagnetized straight away.

Hard magnetic materials (e.g. steel) have domains that do not easily move into line when the metal is placed in a magnetic field, a strong field is needed for some time, but then, when the field is removed the domains retain the magnetic pattern. The metal stays magnetic for a long time.

5 0

3 years ago