In which switching technique, a dedicated

coldgirl [10]

7.5 x 10⁻¹¹m. An electromagnetic wave of frecuency 4.0 x 10¹⁸Hz has a wavelength of 7.5 x 10⁻¹¹m.

Wavelength is the distance traveled by a periodic disturbance that propagates through a medium in a certain time interval. The wavelength, also known as the space period, is the inverse of the frequency. The wavelength is usually represented by the Greek letter λ.

λ = v/f. Where v is the speed of propagation of the wave, and "f" is the frequency.

An electromagnetic wave has a frecuency of 4.0 x 10 ¹⁸Hz and the speed of light is 3.0 x 10⁸ m/s. So:

λ = (3.0 x 10⁸ m/s)/(4.0 x 10¹⁸ Hz)

λ = 7.5 x 10⁻¹¹m

8 0

4 years ago

A 65-kg person stands on a scale in a moving elevator while holding a 5.0 kg mass suspended from a massless spring with spring c

disa [49]

Answer:

The question is incomplete. However, I believe, it is asking for the acceleration of the elevator. This is 3.16 m/s².

Explanation:

By Hooke's law, $F = ke$

F is the force on a spring, k is the spring constant and e is the extension or compression.

From the question,

$F = (1.08\text{ kN/m}) \times (6.0 \times 10^{-2}\text{ m}) = 64.8 \text{ N}$

This is the force on the mass suspended on the spring. Its acceleration, a, is given by

$F = ma$

$a = \dfrac{F}{m}$

$a = \dfrac{64.8 \text{ N}}{5\text{ kg}} = 12.96\text{ m/s}^2$

This acceleration is more than the acceleration due to gravity, g = 9.8 m/s². Hence the elevator must be moving up with an acceleration of

12.96 - 9.8 m/s² = 3.16 m/s²

7 0

3 years ago

There is an increase in energy in all of the following EXCEPT *

mars1129 [50]

Answer:

Freezing

Explanation:

I am pretty sure that the energy particles slow down when they freeze, making it the only one in which energy does NOT increase. Hope I helped.

5 0

3 years ago

A coil with an inductance of 2.8 H and a resistance of 12 Ω is suddenly connected to an ideal battery with ε = 89 V. At 0.086 s

Thepotemich [5.8K]

Answer:

The stored energy is 140.7 watt.

The thermal energy is 62.7 watt.

The delivered energy is 203.4 watt.

Explanation:

Given that,

Inductance = 2.8 H

Resistance = 12 Ω

Potential $\epsilon_{0}=89\ V$

Time = 0.086 s

(a). We need to calculate the energy stored in the magnetic field

Using formula of current

$i=i_{max}(1-e^(\frac{-t}{\tau}))$

Using formula of energy

$U=\dfrac{1}{2}Li^2$

On differentiating

$\dfrac{dU}{dt}=Li\frac{di}{dt}$

$\dfrac{dU}{dt}=L\dfrac{d}{dt}(i_{max}(1-e^(\frac{-t}{\tau}))$

Again differentiating

$\dfrac{dU}{dt}=\dfrac{\epsilon^2}{R}(1-e^{\frac{-t}{\tau}})e^{\frac{-t}{\tau}}$

$\dfrac{dU}{dt}=\dfrac{\epsilon^2}{R}(1-e^{\frac{-\t\times R}{L}})e^{\frac{-t\times R}{L}}$

Put the value into the formula

$\dfrac{dU}{dt}=\dfrac{(89)^2}{12}(1-e^{\dfrac{-0.086\times12}{2.8}})e^{\dfrac{-0.086\times12}{2.8}}$

$\dfrac{dU}{dt}=140.7\ watt$

(b). We need to calculate the thermal energy

Using formula of thermal energy

$P=i^2R$

$P=\dfrac{\epsilon^2}{R}(1-e^{\frac{-t}{\tau}})^2$

Put the value into the formula

$P=\dfrac{89^2}{12}(1-e^{\dfrac{-0.086\times12}{2.8}})^2$

$P=62.7\ Watt$

(c). We need to calculate the delivered energy by the battery

Using formula of energy

$P'=P+\dfrac{dU}{dt}$

$P'=62.7+140.7$

$P'=203.4\ watt$

Hence, The stored energy is 140.7 watt.

The thermal energy is 62.7 watt.

The delivered energy is 203.4 watt.

5 0

4 years ago

What happens to a bowl of hot soup when it is placed into a freezer where the air Temperature is below freezing. How does this a

Artyom0805 [142]

It does not it when put in the freezer it freezes the steam

8 0

3 years ago