(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A Ti-sapphire femtosecond laser (1fs= 10^-15s, λ≈0.8μm) has an intensity of 1022 W/cm2

when focused to a spot of 1μm radius. What is the energy of the laser pulse? What is the peak

magnetic induction B in Tesla and the electric field in V/m? What is the wave pressure in

atmospheres?

2. Relevant equations

[tex]P = \int I da = \frac{E}{\Delta t}[/tex]

[tex]E=cB[/tex]

3. The attempt at a solution

I've solved the first part

[tex]P = IA = 10^{22} \frac{W}{cm^2} \pi \left(1 \mu m\right)^2 [/tex]

[tex] = 3.14 \times 10^{14} W[/tex]

[tex]E = .314 J [/tex]

But what is the relationship of what was given to either ]E or B? The only equations I can find are sinusoidal with the assumption that [tex]E_0[/tex] or [tex]B_0[/tex] are known to find their values at a particular time. Would I take the pulse with the assumption that B and E = 0 and the beginning and end and the information of the wavelength to find the value it peaks at? Now that I'm thinking of that, I'd still need some sort of E_0 or B_0.

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# Homework Help: Energy, magnitude of E & B, pressure from a laser

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