If, for some reason such as economy, we are not going to develop aircraft nuclear propulsion with a sense of national urgency, then we should turn our effort to developing jet engines with a thrust-to-weight ratio of 12 or 15 to one.

If the nominal compression ratio of an engine is given, the pre-ignition cylinder pressure can be estimated using the following relationship:

If we think of the atoms as impenetrable steel discs and the impinging particle as a bullet of negligible diameter, this ratio is the probability that the bullet will strike a steel disc, i. e., that the atomic projectile will be stopped by the foil.

If is much smaller than, the mole ratio is almost identical to the mole fraction.

If is much smaller than, the mass ratio is almost identical to the mass fraction.

If the liquid and vapor are not evenly distributed across the superficial tower area as it enters the packed bed, the liquid to vapor ratio will not be correct in the packed bed and the required separation will not be achieved.

If a petrol engine were to have the same compression ratio, then knocking ( self-ignition ) would occur and this would severely reduce the efficiency, whereas in a Diesel engine, the self ignition is the desired behavior.

If this ratio is 1, the evidence is indifferent,

If a and b are distances from the fulcrum to points A and B and if force F < sub > A </ sub > applied to A is the input force and F < sub > B </ sub > exerted at B is the output, the ratio of the velocities of points A and B is given by a / b, so the ratio of the output force to the input force, or mechanical advantage, is given by

If the group of atoms is in thermal equilibrium, it can be shown from thermodynamics that the ratio of the number of atoms in each state is given by a Boltzmann distribution:

If the lifetime of this transition, τ < sub > 21 </ sub > is much longer than the lifetime of the radiationless 3 → 2 transition τ < sub > 32 </ sub > ( if τ < sub > 21 </ sub > ≫ τ < sub > 32 </ sub >, known as a favourable lifetime ratio ), the population of the E < sub > 3 </ sub > will be essentially zero ( N < sub > 3 </ sub > ≈ 0 ) and a population of excited state atoms will accumulate in level 2 ( N < sub > 2 </ sub > > 0 ).

If the component is a resistor with time-invariant voltage to current ratio, then:

If the producers chose to reformat the entire show for the 16: 9 ratio, live-action footage would have to be recropped, widening the frame to the full width of the 35 mm negatives while reducing its height.

If the ratio of the two resistances in the known leg is equal to the ratio of the two in the unknown leg, then the voltage between the two midpoints ( B and D ) will be zero and no current will flow through the galvanometer.

If the initial amount of Sr is known or can be extrapolated, the age can be determined by measurement of the Rb and Sr concentrations and the < sup > 87 </ sup > Sr /< sup > 86 </ sup > Sr ratio.

If the net gain is expressed as a ratio, and the ratio is less than unity, a net loss is indicated.

If a signal is present, then this factor represents the decrease in signal to noise ratio incurred using the receiver system with a noise temperature of.

If q is the product of that curvature with the circle's radius, signed positive for epi-and negative for hypo -, then the curve: evolute similitude ratio is 1 + 2q.

If the signal and the noise are measured across the same impedance, then the SNR can be obtained by calculating the square of the amplitude ratio:

If two goods are perfect substitutes then the indifference curves will have a constant slope since the consumer would be willing to switch between at a fixed ratio.

If the accuracy ratio is less than 4: 1, then the calibration tolerance can be reduced to compensate.

If we let them go, they won't stay away, they'll find men to ride with them and they'll be back.

If she, Pamela, were being held responsible for his crimes, then hers must be the final act of expiation.

If you don't leave this country within 3 days, your life will be taken the same as Powell's was.

If I hadn't got Nate stopped when I did, my duds'd all be shot plumb to hell!!

`` If you will pardon, I think it would be better if not.

If he showed signs of collecting his rifle and going back with his deputy to the ranch he would be shot down instantly.

If the circumstances are faced frankly it is not reasonable to expect this to be true.

If communications work, his decision would be instantly known in all command posts that would originate the actual go order.

If his dancers are sometimes made to look as if they might be creatures from Mars, this is consistent with his intention of placing them in the orbit of another world, a world in which they are freed of their pedestrian identities.

If the Union conceded this to them, the same right must be conceded to each remaining state whenever it saw fit to secede: This would destroy the federal balance between it and the states, and in the end sacrifice to the sovereignty of the states all the liberty the citizens had gained by their Union.

If an automobile were approaching him, he would know what was required of him, even though he might not be able to act quickly enough.

If life and death did not both present themselves to us, there would be no inscrutability.

If there were only darkness, all would be clear.

If there were only the mess, all would be clear ; ;

If he is good, he may not be legal ; ;

If the existent form is to be retained new factors that reinforce it must be introduced into the situation.

If I now risk some comparisons with Sons And Lovers let it be clear that I am not comparing the two works or judging their merits ; ;

If many of the characters in contemporary novels appear to be the bloodless relations of characters in a case history it is because the novelist is often forgetful today that those things that we call character manifest themselves in surface behavior, that the ego is still the executive agency of personality, and that all we know of personality must be discerned through the ego.

If our sincerity is granted, and it is granted, the discrepancy can only be explained by the fact that we have come to believe hearsay and legend about ourselves in preference to an understanding gained by earnest self-examination.

If in any one calculation Ptolemy had had to invoke 83 epicycles all at once, while Copernicus never required more than one third this number, then ( in the sense obvious to Margenau ) Ptolemaic astronomy would be simpler than Copernican.

If to be innocent is to be helpless, then I had been -- as are we all -- helpless at the start.

If `` Jack the Courtier '' is really to be taken as Swift, the following remark is obviously Steele's comment on Swift's change of parties and its effect on their friendship: `` I assure you, dear Jack, when I first found out such an Allay in you, as makes you of so malleable a Constitution, that you may be worked into any Form an Artificer pleases, I foresaw I should not enjoy your Favour much longer ''.