Science: Which statement is true about star A

Giving me the points are enough <br>

N76 [4]

Answer:

the product of mass and velocity

....in my syllabus

7 0

3 years ago

A speaker is designed for wide dispersion for a high frequency sound. What should the diameter of the circular opening be in a s

Greeley [361]

Answer:

$a = 4.76 cm$

Explanation:

As we know by the law of diffraction through circular aperture

$a sin\theta = 1.22 \lambda$

here we know that

a = diameter of the aperture

$\theta$ = diffraction angle

$\lambda$ = wavelength

now we have

$a = \frac{1.22 \lambda}{sin\theta}$

Now in order to find the wavelength we know

$\lambda = \frac{c}{f}$

$\lambda = \frac{343}{9100}$

$\lambda = 0.0376 m$

now we have

$a = \frac{1.22(0.0376)}{sin75}$

$a = \frac{0.046}{0.966}$

$a = 0.0476 m= 4.76 cm$

6 0

3 years ago

A. A ball is thrown directly up with an initial speed of 4.00 m/s at y = 0. What is the maximum height h that it achieves, and w

sveta [45]

Answer:

A) t = 0.40816 s , y = 0.916 m

Explanation:

A) For this problem we use the kinematic relations

v = v₀ - g t

the highest point zero velocities (v = 0)

t = (v₀-v) / g

t = (4 - 0) / 9.8

t = 0.40816 s

to calculate the height let's use

v² = v₀² - 2 g y

y = vo2 / 2g

y = 4 2 / (2 9.8)

y = 0.916 m

To find the number of photos, we can use a direct proportions rule, if you take 30 photos in a second in 0.40816 s how many photos does it take

# _photos1 = 0.40916 (30/1)

# _photos1 = 12

yes i take 120 fps

#_fotod = 0.40916 (120/1)

#photos = 5.87 10³

B) The ball is released from a latura h how long it takes to reach the floor

v² = v₀² + 2 g y

where the initial velocity is zero and the velocity with which the expert leaves is equal to the velocity with which v = 4 m / s leaves

v² = 2gy

v = √ (2 9.8 0.916)

v = √ (2.1397 101)

v = 4.6257 m / s

c) we ask us for the time for latura

y = L / 2

y = 0.916 / 2

y = 0.458 m

now we can use the formula

y = v₀ t - ½ g t²

0.458 = 4.00 t - ½ 9.8 t²

4.9 t² - 4t + 0.458 = 0

t² -0.8163 t +0.09346 = 0

we solve second degree execution

t = [0.8163 ±√ (0.8163² - 4 0.09346)] / 2

t = [0.8163 ± 0.540] / 2

t₁ = 0.678 m

t₂ = 0.2763 m

the shortest time is for when the ball goes up and the longest when it goes down

D) the graph of vs Vs is expected to be a closed line

and the graph of position versus time a parabola

0 0

3 years ago

The Drude model uses Newton’s laws, which say that an electron in a constant electric field should experience constant accelerat

Troyanec [42]

Answer:

Electrons are influenced by internal forces.

-On the temperature, density of electrons per unit of volume and relaxation time.

-The temperature

Explanation:

The Drude model neglects interactions between electrons and ions and with themselves. Those interactions (by which we refer as electromagnetic forces) influence in the random movement and freedom of the electron. So, they could be more restricted or could influence in conductivity more.

The deduction of the resistivity comes from the Ohm's law, which states that the Electric field in the material is proportional to the current density of electrons by a constant, which is the resistivity itself. The equation goes as follows:

$\rho=\frac{m_e}{e^2n_e \tau }$

Where e refers to electron (or the charge of it), τ is the relaxation time (average time between collisions), m is the mass and n is the density of charges (electrons in this case) per volume. However, experimentally resistivity is also dependent on temperature, which actually influence the relaxation time. The thermal energy influence in the behavior of the electrons, making them collide with phonons, have more randomness and reduced mean free path.

6 0

3 years ago

What is the chemical formula for ammonium hydroxide

hoa [83]

NH4OH is the answer. Hope this helps you.

8 0

2 years ago