Match the correct term with the statement that is true about it

The Doppler effect occurs when a source of sound moves

Dmitrij [34]

The Doppler effect occurs when a source of sound or light
moves either toward or away from the observer.

4 0

3 years ago

The position of a particle as it moves along an y axis is given by y = (2.0cm)sin(πt/4), with t in second and y in centimeters.

irina [24]

Part a)

At t = 0 the position of the object is given as

$x = 0$

At t = 2

$x = 2 sin(\pi/2) = 2cm$

so displacement of the object is given as

$d = 2 - 0 = 2cm$

so average speed is given as

$v_{avg} = \frac{2}{2} = 1 cm/s$

Part b)

instantaneous speed is given by

$v = \frac{dy}{dt}$

$v = 2cos(\pi t/4 ) * \frac{\pi}{4}$

now at t= 0

$v = \frac{\pi}{2} cm/s$

at t = 1

$v = 2 cos(\pi/4) * \frac{\pi}{4}$

$v = \frac{\pi}{2\sqrt2}$

at t = 2

$v = 0$

Part c)

Average acceleration is given as

$a_{avg} = \frac{v_f - v_i}{t}$

$a_{avg} = \frac{0 - \frac{\pi}{2}}{2}$

$a = -\frac{\pi}{4} cm/s^2$

Part d)

Now for instantaneous acceleration

As we know that

$a =- \omega^2 y$

at t = 0

$a = -\frac{\pi^2}{16} * 0 = 0 cm/s^2$

at t = 1

$y = \sqrt2 cm$

now we have

$a = -\frac{\pi^2}{16}*\sqrt2$

At t = 2 we have

$y = 2 cm$

$a = -\frac{\pi^2}{16}*2$

$a = -\frac{\pi^2}{8}$

so above is the instantaneous accelerations

7 0

3 years ago

Romeo (81.0 kg) entertains Juliet (53.0 kg) by playing his guitar from the rear of their boat at rest in still water, 2.70 m awa

den301095 [7]

Answer:

0.64 m

Explanation:

The first thing is calculate the center of mass of the system.

$X_{cm}= \sum_{n=1}^{n}\frac{X_n\times M_n}{M_n}$

now multiplying every coordinate x by the mass of each object (romeo, juliet and the boat) and dividing all by the total mass taking by reference the position of juliet.

$X_{cm}=\frac{53\times0 +81\times2.7+79\times1.35}{53+81+79}$

X_cm = 1.4589 m

When the forces involved are internals, the center of mass don't change

After the movement the center of mass remains in the same distance from the shore, but change relative to the rear of the boat.

$X_{cm}=\frac{79\times1.35+(81+53)\times2.7}{53+81+79}$

X_cm= 2.10 m

this displacement is how the boat move toward the shore.

2.10-1.46= 0.64 m

5 0

3 years ago

Which of the following has the greatest magnitude? 30 Newtons 1 Newton . 10 Newtons

Zinaida [17]

Answer:

30 newtons

Explanation:

5 0

2 years ago

Atoms with certain characteristics are radioactive. Which is least likely to be radioactive? O A. all atoms with an atomic numbe

Luden [163]

Answer:

The answer an be the option A.

Explanation:

Because radioactive substances have atomic number greater than 82.

8 0

2 years ago