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2 years ago

Which type of surface is best for absorbing sound waves?

Physics

2 answers:

sergiy2304 [10]2 years ago

6 0

I think it's B (foam) it may not be though

weeeeeb [17]2 years ago

4 0

I believe it is D) foam

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A metal ring 4.60 cm in diameter is placed between the north and south poles of large magnets with the plane of its area perpend

telo118 [61]

Answer:

A. Ein = 8.05*10^-4 V/m

B. Clockwise sense

Explanation:

A. the magnitude of the electric field induced in the ring is obtaind by using the following formula:

$\int E_{in} \cdot ds=-\frac{d\Phi_B}{dt}$ (1)

Ein: induced electric field

ds: differential of a path of the ring

ФB: magnetic flux in the ring

The Ein vector is parallel to ds in the complete ring. Furthermore, the area of the ring is constant, hence, you have in the equation (1):

$\int E_{in}ds=E_{in}(2\pi r)=-A\frac{dB}{dt}\\\\E_{in}=-\frac{A}{2\pi r}\frac{dB}{dt}$ (2)

dB/dt = -0.280T/s (it is decreasing)

A: area of the ring = π(r/2)^2= (π/4) r^2

r: radius of the ring = 4.60/2 = 2.30 cm

Then, you replace the values of all variables in the equation (2):

$E_{in}=-\frac{(\pi/4)r^2}{2\pi r}\frac{dB}{dt}=\frac{r}{8}\frac{dB}{dt}\\\\E_{in}=-\frac{0.0230m}{8}(-0.280T)=8.05*10^{-4}\frac{V}{m}$

hence, the induced electric field is 8.05*10^-4 V/m

B. The induced current in the ring produced a magnetic field that is opposite to the magnetic field of the magnet. The, in this case you have that the induced current is in a clockwise sense.

6 0

4 years ago

Speed is a vector quantity. Do you agree? Justify your answer.

abruzzese [7]

Answer:

Explanation:

because speed is the rate of change in the distance travelled by an object

so, speed is scalar quantity.

<h2>Mark me as brainlist</h2>

8 0

3 years ago

Read 2 more answers

I need help on a english book report

lianna [129]

Answer:

I can help, but

Explanation:

Where is the question?

7 0

2 years ago

You are driving your car along a country road at a speed of 27.0 m/s. as you come over the crest of a hill, you notice a farm tr

Bezzdna [24]

speed of the car = 27 m/s

speed of truck ahead = 10 m/s

relative speed of car with respect to truck

$v_r = 27 - 10 = 17 m/s$

relative deceleration of car

$a_r = -7 m/s^2$

now the distance before they stop with respect to each other is given by

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

$0 - 17^2 = 2 *(-7)*d$

$d = 20.6 m$

so it will come at the same speed of truck after 20.6 m distance and hence it will not hit the truck as the distance of the truck is 25 m from car

Part b)

Distance traveled by car before it stops is given by

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

$0^2 - 27^2 = 2 * (-7)* s$

$s = 52.1 m$

so it will stop after it will cover total 52.1 m distance

Part c)

time taken by the car to stop

$v_f - v_i = at$

$0 - 27 = (-7) * t$

$t = 3.86 s$

now the distance covered by truck in same time

$d = 3.86 * 10 = 38.6 m$

now after the car will stop its distance from the truck is

$D = 25 + 38.6 - 52.1 = 11.5 m$

<em>so the distance between them is 11.5 m</em>

6 0

3 years ago

A small rocket to gather weather data is launched straight up. Several seconds into the flight, its velocity is 140 m/s and it i

Free_Kalibri [48]

Explanation:

The force will be 98 N....

7 0

3 years ago