Answer:
the planes times in the air
Explanation:
When a paper airplane is thown the path it takes is not the same every time. So, measuring the distance between the points where the airplane took off and the point where is landed would not show the time the plane was in the air.
The weight also does not determine the time the plane was in the air.
So, the planes air time recorded with the stopwatch gives the time the plane was in the air and will indicate the best plane.
Answer:
Option B
It converts light into electric current
Explanation:
A photometer is a device used to measure illuminance
Its principle of operation hinges on the conversion of light into electric current, using photoresistor or any other light sensitive device such as a photodiode. This is so that it can be read off easily by any other device.
A Photoresistor is a device that changes the flow of current through it when it is exposed to light rays. A photometer works by irradiating a photo resistor, which then converts the light rays incident on it to electric current.
Draw a vector diagram. The net force on particle 1 = F12 + F13 + F14 These forces have to be added as vectors.
We will resolve our forces along the direction 1-4 F12 (tot) = -kQq / a^2 in the direction of particle 4 F12 = -kQq *sin (45) / a^2 F12 = -kQq /( a^2 * sqrt(2) )
By symetry this is the same as F13 F13 = -kQq /( a^2 * sqrt(2) )
F14 = -kQQ / (Sqrt(2)*a) ^ 2
For net force on particle 1 :
F12+F13+F14 = 0 -2kQq /( a^2 * sqrt(2) ) + -kQQ / (Sqrt(2)*a) ^ 2 = 0
Some simple manipulation should give you :
Q/q = -2 sqrt(2)
Answer: A. If the surface aquifer has a high water table
Explanation:
The water table refers to the water level underground. If it is high, it means that the water underground is close to the surface such that if a well was dug, it would not need to be dug too far for water to be seen.
When heavy rain falls, flooding is avoided if the water is either able to run off efficiently or if the ground is able to absorb the water. When the water table is high, it means that the ground will not be able to absorb much because the water is already close to the surface which means that should heavy rain fall, there will most likely be a flood.
