Answer:Both are correct
Explanation:
Both are correct because
Mechanical efficiency is the dimensionless term which is the ratio of brake horsepower to the Indicated horse Power
Where brake power is the Power obtained at the crankshaft and
Indicated horsepower is the power obtained in the combustion chamber and this power is the loss in the form of friction.
Volumetric efficiency is the ratio of actual fuel intake to the maximum air fuel that could be taken.
Lets assume that s is the speed of the slower train and f is the speed of the faster train.
s = f - 16
f = 150 / t
s = 170 / ( t+2 )
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170 / ( t+2 ) = 150 / t - 16 / t * ( t + 2 )
170 t = 150 * ( t + 2 ) - 16 t * ( t + 2 )
170 t = 150 t + 300 - 16 t² - 32 t
16 f² + 52 t - 300 = 0 / : 4 ( We will divide both sides of the equation by 4 )
4 t² + 13 t - 75 = 0
t 1/2 = ( -13 + √(169 + 1200 ) )/ 8
t = ( - 13 + 37 ) / 8 = 24 / 8 = 3
t = 3 h
s = 170 : ( 3 + 2 ) = 170 : 5 = 34 mph
Answer: The speed of the slower train is 34 mph.
Answer: 9) when water is put inside a pot and put on a stove, the fire heats the pot, heat is transferred through the pot by conduction, the next step here in heat transfer by convection which happens in the water in the pot, when heat is transferred from the pot to the water the water molecules gain kinetic energy and moves up while the heavier molecules of the water comes down to get heated, this continues until heat is transferred throughout the water by convection, radiation occur when the quantity of the water is getting reduced.
10) same principle applies to that of the stove, but the difference is that the heat comes from sun and not from fire, the ice-cream is heated by conduction and heat is spread throughout the ice cream by convection , and radiation comes from the sun to the ice cream
Explanation:
Answer:
The second (abbreviation, s or sec) is the Standard International ( SI ) unit of time. One second is the time that elapses during 9,192,631,770 (9.192631770 x 10 9 ) cycles of the radiation produced by the transition between two levels of the cesium 133 atom. ... One second is equal to 1/86,400 of a mean solar day.
Explanation: