How much have jellyfish populated since 2015?

Two gratings A and B have slit separations dA and dB, respectively. They are used with the same light and the same observation s

77julia77 [94]

Answer:

a) dB / dA = 2 ,

b) Network B Network A

2 1

4 2

6 3

Explanation:

a) The expression for grating diffraction is

d sin θ = m λ

where d the distance between two slits, λ the wavelength and m an integer that represents the diffraction range

In this exercise we are told that the two spectra are in the same position, let's write the expression for each network

Network A

m = 1

sin θ = 1 λ / dA

Network B

m = 2

sin θ = 2 λ / dB

they ask us for the relationship between the distances, we match the equations

λ / dA) = 2 λ / dB

dB / dA = 2

b) let's write the equation of the networks

sin θ = m_A λ / dA

sin θ = m_B λ / dB

we equalize

m_A λ/ dA = m_B λ / dB

we use that

dB / dA = 2

m_A 2 = m_B

therefore the overlapping orders are

Network B Network A

2 1

4 2

6 3

4 0

3 years ago

A cannon shoots a ball at an angle θ above the horizontal ground. (a) Neglecting air resistance, use Newton's second law to find

nikitadnepr [17]

Answer:

a) x = v₀ₓ t , y = $v_{oy}$ t - ½ g t²

Explanation:

This is a projectile launch problem, let's use Newton's second law on each axis

X axis

F = m a

Since there is no acceleration on the x axis, the force on this axis is zero

Y Axis

-W = m $a_{y}$

-m g = m $a_{y}$

$a_{y}$ = -g

In this axis the acceleration is the acceleration of gravity

Now we can use science to find the position of the body on each axis

X axis

x = v₀ₓ t + ½ a t²

As the acceleration on this axis is zero

x = v₀ₓ t

Y Axis

y = $v_{oy}$ t + ½ $a_{y}$ t²

The acceleration on this axis is –g

y = $v_{oy}$ t - ½ g t²

B) to find the maximum value of distance r

r =√ x² + y²

r = √( v₀ₓ² t² + ( $v_{oy}$ t + ½ g t²)²

We can find the maximum value of r using time respect derivatives

dr / dt = 0

0 = ½ 1/√( v₀ₓ² t² + ( $v_{oy}$ t + ½ g t²)² (v₀ₓ² 2t + 2 ( $v_{oy}$ t - ½ g t²)( $v_{oy}$ - ½ g2t)

We simplify this expression

0 = v₀ₓ² 2t + 2 ( $v_{oy}$ t - ½ g t²) ( $v_{oy}$ - ½ g2t)

-v₀ₓ² t =( $v_{oy}$ t - ½ g t²) ( $v_{oy}$ - ½ g2t)

-v₀ₓ² t = $v_{oy}$ ² t -3/2 gt² $v_{oy}$ + 1/2 g² t³

½ g² t²- 3/2 g $v_{oy}$ t = $v_{oy}$ ² + v₀ₓ²

Let's use trigonometry to find go and vox

sin θ = $v_{oy}$ / v₀

cos θ = vox / v₀

$v_{oy}$ = v₀ sin θ

v₀ₓ = v₀ cos θ

We replace

½ g² t² -3/2 g $v_{oy}$ t = v₀ (sin² θ + cos² θ)

g t² - 3v₀ sin θ t = 2 v₀/g

The time is maximum for the angle is zero

8 0

3 years ago

A rod of length L is hinged at one end. The moment of inertia as the rod rotates around that hinge is ML2 /3. Suppose a 2.00-m r

Stels [109]

To solve this problem we will apply the concepts related to the moment of inertia and Torque, the latter both its translational and rotational expression.

According to the information given the moment of inertia of the body would be

$I = \frac{1}{3} mL^2$

Replacing we have

$I = \frac{1}{3} (3kg)(2m)^2$

$I = 4 kg * m^2$

Now the translational torque would be the product between the force applied (Its own Weight) and the distance (Its center of mass at the middle)

$\tau = F*r$

$\tau = mg (\frac{L}{2})$

$\tau = (3)(9.8)(\frac{2}{2})$

$\tau = 29.4N\cdot m$

Now the rotational torque is defined as the product between the moment of inertia and the angular acceleration, then,

$\tau = I\alpha \rightarrow \alpha = \frac{\tau}{I}$

Replacing,

$\alpha = \frac{29.4}{4}$

$\alpha =7.35 rad / s^2$

Therefore the angular acceleration is $7.35rad/s^2$

4 0

3 years ago

Maxwell’s theory of Electromagnetism in 1865 was the first "unified field theory" _________ no further theory has united the ele

Andrei [34K]

Answer: E. and Electroweak in 1961 the only other, as

Explanation:

This is more an English grammar question than a physics question, so taking that perspective, one should look for the answer that best completes the sentence.

Based on the word "first" in the sentence, implying the need for a conjunction to join the two theories and the last part of the sentence does not give a reason but further supports the determination of the theory being the first unified theory.

So, to complete the sentence, the best option is;

Maxwell’s theory of Electromagnetism in 1865 was the first "unified field theory" and Electroweak in 1961 the only other, as no further theory has united the electroweak field with either the Strong (Hadronic) force or Gravity.

6 0

4 years ago

A tetrahedron has an equilateral triangle base with 25.0-cm-long edges and three equilateral triangle sides. The base is paralle

KATRIN_1 [288]

Answer:

electric flux through the three side = 2.35 N m²/C

Explanation:

given,

equilateral triangle of base = 25 cm

electric field strength = 260 N/C

Area of triangle = $\dfrac{\sqrt{3}}{4}a^2$

= $\dfrac{\sqrt{3}}{4} 0.25^2$

= 0.0271 m³

electric flux = E. A

= 260 × 0.0271

= 7.046 N m²/C

since, tetrahedron does not enclose any charge so, net flux through tetrahedron is zero.

electric flux through the three side = (electric flux through base)/3

= $\dfrac{7.046}{3}$

electric flux through the three side = 2.35 N m²/C

4 0

3 years ago