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3 years ago

Please answer correctlywill give the brainliestUrgent

Physics

1 answer:

EastWind [94]3 years ago

3 0

Answer:

f (frequency) = V / y where V is the speed of sound and y the wavelength

f = 1500 m/s / 1.5 m = 1000 / sec

T (period) = 1 / f = .001 sec

Suppose you replace the horn by a drum then the period would be the time between the beats of the drum - now if the source is moving towards the observer then the distance between crests of the wave produced by the drum will be shortened by V * T because of the motion of the drum "towards" the observer, and since the wavelength is shorter the frequency heard by the observer will be higher, and the higher the speed of of the car the shorter the wavelength as seen by the observer and the higher the frequency.

Also, if the car is moving away from the observer then the distance between the crests of the wave emitted will be further apart, and the observer will hear a lower frequency.

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A motorcycle stunt driver zooms off the end of a cliff at a speed of 41.9 meters per second. If he lands after 1.62 seconds, wha

tiny-mole [99]

Of the cliff?

Projectile motion
In the problem we are asked to find a height of certain cliff when a motorcycle stunt driver zoom out horizontally at the end the cliff at an initial velocity. So we will use one of the kinematics equation for projectile motion,

y
=
v
o
y
t
+
1
2
g
t

where
v
o
y
is just equal to zero since we can assume that the driver zooms out horizontally,
g
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9.8

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8 0

3 years ago

Which of the following factors will negatively impact the rate of diffusion of a molecule?

Maurinko [17]

Answer:

A low difference in the concentration of the molecule across the media

Explanation:

Diffusion is a type of passive transport where the molecules move in the influence of concentration gradient of diffusing molecules i.e. from the higher concentration region to the lower concentration region. There are some factors which affect the rate of diffusion, these are written below -

Mass of diffusing molecule - lighter molecules diffuse faster and heavier one diffuse relatively slower.
Concentration gradient - rate of diffusion is higher if the difference in concentration of the diffusing particles is larger in the two regions.
Distance traveled - molecules diffuse faster if they need to travel little distance during diffusion.
Temperature - rate of diffusion will be greater at higher temperatures because the movement of diffusing molecules gets increased.
Solvent density - rate of diffusion tend to be lower if the solvent has higher density.

Looking at these factors we can conclude that the second statement in the question tells about a negative impact regarding the diffusion because due to low difference in concentration across the two media, the rate of diffusion will be lower.

3 0

3 years ago

For what absolute value of the phase angle does a source deliver 71 % of the maximum possible power to an RLC circuit

kherson [118]

Answer: the absolute value of the phase angle is 28°

Explanation:

taking a look at expression for the instantaneous electric power in an AC circuit;

P = VI -------let this be equation 1

p is power, v is voltage and I is current;

for maximum power

P_max = V_rms × I_rms --------let this be equ 2

where P_max is the maximum power, V_rms is the rms value of voltage and I_rms is the rms value of current.

Also for average electric power in an AC circuit

P_avg = V_rms × I_rms × cos²∅ -------let this be equ 3

where P_avg is the average power and cos∅ is the power factor

now from equation 2; P_max = V_rms × I_rms

so p_max replaces V_rms × I_rms in equation 3

we now have

P_avg = P_max × cos²∅

so we substitute

expression for the given value of the average power is

P_avg = P_max × 75%

p_avg = P_max.78/100

for the expression of the average electricity in an AC circuit

P_max.78/100 = P_max × cos²∅

78/100 = cos²∅

to get the absolute value of phase angle

∅ = cos⁻¹ ( √(78/100))

∅ = cos⁻¹ ( 0.8832)

∅ = 27.969 ≈ 28°

Therefore the absolute value of the phase angle is 28°

8 0

2 years ago

The weight of a block on the inclined plane is 500 N and the angle of incline is 30 degrees. What is the magnitude of the force

yanalaym [24]

Answer:

250 N

433 N

Explanation:

N = Normal force by the surface of the inclined plane

W = Weight of the block = 500 N

f = static frictional force acting on the block

Parallel to incline, force equation is given as

f = W Sin30

f = (500) Sin30

f = 250 N

Perpendicular to incline force equation is given

N = W Cos30

N = (500) Cos30

N = 433 N

3 0

3 years ago

It takes a minimum distance of 57.46 m to stop a car moving at 13.0 m/s by applying the brakes (without locking the wheels). Ass

vivado [14]

Answer:

The minimum stopping distance when the car is moving at

29.0 m/sec = 285.94 m

Explanation:

We know by equation of motion that,

$v^{2}=u^{2}+2\cdot a \cdot s$

Where, v= final velocity m/sec

u=initial velocity m/sec

a=Acceleration m/ $Sec^{2}$

s= Distance traveled before stop m

Case 1

u= 13 m/sec, v=0, s= 57.46 m, a=?

$0^{2} = 13^{2} + 2 \cdot a \cdot57.46$

a = -1.47 m/ $Sec^{2}$ (a is negative since final velocity is less then initial velocity)

Case 2

u=29 m/sec, v=0, s= ?, a=-1.47 m/ $Sec^{2}$ (since same friction force is applied)

$v^{2} = 29^{2} - 2 \cdot 1.47 \cdot S$

s = 285.94 m

Hence the minimum stopping distance when the car is moving at

29.0 m/sec = 285.94 m

4 0

3 years ago

Please answer correctlywill give the brainliestUrgent​

Please answer correctlywill give the brainliestUrgent