Which one of the following violate the law of conservation of momentum Mass before: 5 kg, velocity before: 3 m/s mass after: 6 kg, velocity after: 2 m/s

Mass before: 4 kg, velocity before: 3 m/s mass after: 3 kg, velocity after: 4 m/s

mass before: 4 kg, velocity before: 3 m/s mass after: 6 kg, velocity after: 2 m/s

a) All
b) None
c) Bottom only
d) Top only

Hydrogen atoms are excited by a laser to the =4n=4 state and then allowed to emit. what is the maximum number of distinct emission spectral lines (lines of different wavelengths) that can be observed from this system? 8 6 2 7 4 5 1 3 calculate the wavelength of the 4⟶14⟶1 transition. =λ=

Aprotein molecule in an electrophoresis gel has a negative charge. the exact charge depends on the ph of the solution, but 30 excess electrons is typical. what is the magnitude of the electric force on a protein with this charge in a 1600n/c electric field? write in two significant numbers, and also in newton

Engines for propeller-driven aircraft are limited in their maximum rotational speed by the fact that the tip speed of the propeller must not approach the speed of sound in air (mach i). taking 6 ft as a typical diameter for a propeller of a light airplane and 1100 fils as the speed of sound, find the upper limit on the rpm (revolutions per minute) of the propeller shaft.