Answer: The average speed is 27,24 mph (exactly 1008/37 mph)
Explanation:
This is solved using a three rule: We know the speeds and the distances, what we can obtain from it is the time used. It is done like this:
1h--->18mi
X ---->20 mi, then X=20mi*1h/18mi= 10/9 h=1,111 h
1h--->56mi
X ---->20 mi, then X=20mi*1h/56mi= 5/14 h=0,35714 h
Then the average speed is calculated by taking into account that it was traveled 40mi and the time used was 185/126 h=1,468 h and since speed is distance over time we get the answer. Average speed= 40mi/(185/126 h)=1008/37 mph=27,24 mph.
If this case could ever happen, the speed would follow from this formula:
with f the frequency and lambda the wavelength. We are give a wavelength of 10m. The frequencies of the visible light can range between 400 to about 790 Terahertz, so let us pick a middle point of 600 THz ("green-ish") as a "representative."
The speed of such a wave would have to be 6e+15 m/s (which would be 7 orders of magnitude higher than the universal speed of light constant)
Answer:
acceleration
Explanation:
The rate at which velocity changes is the definition of the physical quantity called acceleration, and it is given by the formula: 
where 
is the time that took to change from the initial velocity 
to the final velocity 
Most reactions are exothemic. If the forward reaction of an equilibrium reaction is exothemic then the reverse reaction must be endothermic.
If a system in equilibrium is heated, it will move in exothermic direction to give out heat energy.
Answer:
0.0195 m
Explanation:
= density of hockey puck = 9.45 gcm⁻³ = 9450 kgm³
= diameter of hockey puck = 13 cm = 0.13 m
= height of hockey puck = 2.8 cm = 0.028 m
= density of mercury = 13.6 gcm⁻³ = 13600 kgm³
= depth of puck below surface of mercury
According to Archimedes principle, the weight of puck is balanced by the weight of mercury displaced by puck
Weight of mercury displaced = Weight of puck
