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2 years ago

Fill in the blanks to complete the statements.

Physics

1 answer:

Murljashka [212]2 years ago

3 0

Answer:

When an object changes speed (increases/decreases) it results in acceleration/de acceleration, its velocity also changes.

Explanation:

Acceleration is the rate of change in velocity.An object can accelerate when speed increases, decreases or direction changes. All these instances involves a change in velocity.Velocity is a vector quantity thus it has magnitude and the direction.Acceleration due to change in direction is centripetal acceleration.The expression for finding acceleration is;

a=change in velocity/change in time

a=Δv/Δt in m/s²

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un serbatoio d'acqua di forma cilindrica è riempito con acqua dolce fino a un livello di 6,40 m calcola la pressione dell'acqua

ohaa [14]

Per calcolare la pressione a una certa profondità, devi considerare la legge di Stevino:
p = ρ · g · h

Tenendo conto che:
g = 9,81 m/s²
ρ = 1000 kg/m³

Troviamo:
p(h₁) = ρ · g · h₁ = 1000 · 9,81 · 4,50 = 44145 Pa
p(h₂) = ρ · g · h₂ = 1000 · 9,81 · 5,50 = 53955 Pa

6 0

2 years ago

Chromatic aberration comes from the fact that different wavelengths of light travel at different speeds through the material of

gtnhenbr [62]

Answer:

y_red / y_blue = 1.11

Explanation:

Let's use the constructor equation to find the image for each wavelength

1 /f = 1 /o + 1 /i

Where f is the focal length, or the distance to the object and i the distance to the image

Red light

1 / i = 1 / f - 1 / o

1 / i_red = 1 / f_red - 1 / o

1 / i_red = 1 / 19.57 - 1/30

1 / i_red = 1,776 10-2

i_red = 56.29 cm

Blue light

1 / i_blue = 1 / f_blue - 1 / o

1 / i_blue = 1 / 18.87 - 1/30

1 / i_blue = 1,966 10-2

i_blue = 50.863 cm

Now let's use the magnification ratio

m = y ’/ h = - i / o

y ’= - h i / o

Red Light

y_red ’= - 5 56.29 / 30

y_red ’= - 9.3816 cm

Light blue

y_blue ’= 5 50,863 / 30

y_blue ’= - 8.47716 cm

The ratio of the height of the two images is

y_red ’/ y_blue’ = 9.3816 / 8.47716

y_red / y_blue = 1,107

y_red / y_blue = 1.11

5 0

2 years ago

Consider a capacitor made of two rectangular metal plates of length and width , with a very small gap between the plates. There

mezya [45]

Answer:

F= σ² L² /2ε₀

F = (L² ε₀/4π) ΔV² / r⁴

Explanation:

a) For this exercise we can use Coulomb's law

F = - k Q² / r²

where the negative sign indicates that the force is attractive and the value of the charge is equal to the two plates

Capacitance is defined by

C = Q / ΔV

Q = C ΔV

also the capacitance for a parallel plate capacitor is related to its shape

C = ε₀ A / r

we substitute

Q = ε₀ A ΔV / r

we substitute in the force equation

F = k (ε₀ A ΔV / r)² / r²

k = 1 / 4πε₀

F = ε₀ /4π L² ΔV² / r⁴4

F = L² ΔV² ε₀/ (4π r⁴)

F = (L² ε₀/4π) ΔV² / r⁴

b) Another way to solve the exercise is to use the relationship between the force and the electric field

F = q E

where we can calculate the field created by a plane using Gaussian law, where we use a cylinder with a base parallel to the plate as the Gaussian surface

Ф = ∫E .dA = $q_{int}$ / ε₀

the plate have two side

2E A = q_{int} / ε₀

E = σ / 2ε₀

σ = q_{int} / A

substituting in force

F = q σ / 2ε₀

the charge total on the other plate is

q = σ A

q = σ L²

F= σ² L² /2ε₀

4 0

2 years ago

16. A 7500 kg 18-wheeler traveling at 20 m/s exits onto the runaway truck ramp on the freeway.

miskamm [114]

Answer:

765,000 Joule

Explanation:

Principle of Conservation of Energy

The total energy in an isolated system cannot be created or destroyed, but transformed. Moving objects have kinetic energy, objects placed in some height above a reference level have gravitational potential energy. When they change their motion variables, one energy converts into the other, but if the numbers don't fit, we know there was some other type of energy acting into the system. The most common reason for energy 'losses' is the thermal energy, produced when objects move in rough surfaces or take friction from the air.

The 7,500 kg truck is originally traveling at 20 m/s to a certain height we'll set to 0. Thus, its total energy is

$\displaystyle E_1=\frac{mv^2}{2}$

$\displaystyle E_1=\frac{7,500\ 20^2}{2}$

$E_1=1,500,000\ Joule$

When it comes to a stop, its speed is 0 and its height is 10 m higher than before. It means all the kinetic energy was transformed into other types of energy. The gravitational potential energy is

$U=mgh=(7,500)(9.8)(10)=735,000\ Joule$