The wavelength of a ruby laser is 694.3 nm
What is the energy difference between the two energy states involved in laser action? (c = 2.9979 × 108 m/s, h = 6.626 × 10-34 J ? s, 1 eV = 1.6022 × 10-19 J)
A) 1.537 eV
B) 1.646 eV
C) 1.786 eV
D) 1.812 eV
E) 3.572 eV
C
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A series RLC circuit connected across an ac voltage source will have a positive value of the phase angle at high frequencies
Indicate whether the statement is true or false
In a Newtonian fluid, the viscosity is equal to
(a) The applied shear stress divided by the shear strain. (b) The applied shear stress times the shear strain rate. (c) The shear strain rate divided by the applied shear stress. (d) The applied shear stress divided by the shear strain rate.
A pickup truck moves 25. m/s Eastward. Jerry is standing in the back and throws a baseball in what to him is the Southwest direction at 28. m/s (with respect to the truck). A person at rest would see the ball moving HOW FAST in WHAT DIRECTION?
What will be an ideal response?
A robot spacecraft is sent to Mars to explore the Martian polar ice cap. Designers can surround it with a set of inflatable balloons that pop out like automobile air bags as soon as the spacecraft's re-entry parachute opens up. 
When the spacecraft lands, it will be able to roll for a few meters across the surface of Mars. The popout balloons have an advantage to the spacecraft, because
A. they increase the time of impact and lessen the stopping force. B. they cancel out the normal force of the surface of Mars. C. the impulse that stops the spacecraft for landing is less with these balloons. D. they decrease the kinetic energy.