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3 years ago

A car speeds past you sounding its horn at a frequency of 1000Hz. The frequency you hear:

Physics

1 answer:

ki77a [65]3 years ago

3 0

Answer:

f' =1064.1025 Hz

Explanation:

We know that from doppler's effect

$f'=\frac{v+v_0}{v-v_s}f$

f'= observed frequency

f= actual frequency =1000 Hz

v= velocity of sound waves = 332 m/s

v_o= velocity of observer =0

v_s= velocity of source. ( let velocity of car be 20 m/s)

therefore,

$f'=\frac{332+0}{332-20}\times1000$

f' =1064.1025 Hz

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slader Question: A Model Rocket Is Launched Straight Upward With An Initial Speed Of 50m/s. Iit Accelerates With A Constant Upwa

xenn [34]

Answer:

Maximum height reached by the rocket is

$y_{max} = 308 m$

total time of the motion of rocket is given as

$T = 16.44 s$

Explanation:

Initial speed of the rocket is given as

$v_i = 50 m/s$

acceleration of the rocket is given as

$a = 2 m/s^2$

engine stops at height h = 150 m

so the final speed of the rocket at this height is given as

$v_f^2 - v_i^2 = 2 a d$

$v_f^2 - 50^2 = 2(2)(150)$

$v_f = 55.68 m/s$

so maximum height reached by the rocket is given as the height where its final speed becomes zero

so we will have

$v_f^2 - v_i^2 = 2 a d$

$0 - 55.68^2 = 2(-9.81)(y - 150)$

$y_{max} = 308 m$

Now the total time of the motion of rocket is given as

1) time to reach the height of 150 m

$v_f - v_i = at$

$55.68 - 50 = 2 t$

$t_1 = 2.84 s$

2) time to reach ground from this height

$\Delta y = v_y t + \frac{1}{2}gt^2$

$-150 = 55.68 t - \frac{1}{2}(9.81) t^2$

$t_2 = 13.6 s$

so total time of the motion of rocket is given as

$T = 13.6 + 2.84 = 16.44 s$

3 0

3 years ago

What is a good activity for strengthening your stomach muscles?

koban [17]

Answer:

sit-ups

Explanation:

3 0

3 years ago

Read 2 more answers

What is the difference between a free body diagram and a vector diagram?

Murrr4er [49]

Answer:

Free body diagrams are used to describe situations where several forces act on an object. On the other hand Vector diagrams are used to resolve (break down) a single force into two forces acting as right angles to eachother

Explanation:

Hope this helps !

4 0

2 years ago

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If an impulse of 400 Ns acts on an object for 15s, what is the force of the object?

Ksju [112]

Answer:

J for impulse

t for time

F for force

formula is J=F×t

Explanation:

putting values in eqs after rearranging

we need to find force so

F=J ÷t

F=400÷15

=26.67

=27(rounded off)

27N is the Force applied.

7 0

3 years ago

A long iron bar lies along the x-axis and has current of I = 16.4 A running through it in the +x-direction. The bar is in the pr

Gre4nikov [31]

Answer:

B = 8.0487mT

Explanation:

To solve the exercise it is necessary to take into account the considerations of the Magnetic Force described by Faraday,

The magnetic force is given by the formula

$F =BILsin\theta$

Where,

B = Magnetic Field

I = Current

L = Length

$\theta =$ Angle between the magnetic field and the velocity, for this case are perpendicular, then is 90 degrees

According to our data we have that

I = 16.4A

F = 0.132N/m

As we know our equation must be modificated to Force per length unit, that is

$\frac{F}{L} = BI sin(90)$

Replacing the values we have that

$0.132 = 16.4 (1) B$

Solving for B,

$B = \frac{0.132}{16.4}$

$B = 8.0487mT$

8 0

3 years ago