Answer:
2.083 V.
Explanation:
Stopping potential is the potential that is required to stop the current to zero . This potential is applied externally to oppose the potential created by the photoelectric effect . It gives the measure the photoelectric potential being generated .
Here current drops to 25 μA to 19 μA by a potential of 500mV
Change in current
= 25 - 19 = 6 μA
Voltage requirement for unit reduction in current
= 500 / 6 μA
To reduce current 0f 25 μA
requirement of V = (500 / 6 ) x 25 = 2083.33 mV = 2.083 V.
Electric pumps are not useful they clog
Answer:
(a). The average daily demand of this subdivision is 2444.44 gallon/min.
(b). The design-demand used to design the distribution system is 2444.44 gallon/min.
Explanation:
Given that,
Area = 1100 acres
Number of house in 1 acres = 4


Per house water demand = 800 g/day/house
(a). We need to calculate the average daily demand of this subdivision
Using formula for average daily demand





The average daily demand of this subdivision is 2444.44 gallon/min.
(b). We need to calculate the design-demand used to design the distribution system
Using formula for the design-demand



Hence, (a). The average daily demand of this subdivision is 2444.44 gallon/min.
(b). The design-demand used to design the distribution system is 2444.44 gallon/min.
Answer:
d) 0 V
Explanation:
It can be showed that the potential due to a point charge q, to a distance d from the charge, can be expressed as follows:

where k = 
As the potential is an scalar, and is linear with the charge, we can apply the superposition principle, which means that we can find the potential due to one of the charges, as if the other were not present.
By symmetry, all four charges are at the same distance from the center, so we can write the total potential, as follows:

where d, is the semi-diagonal of the square, that we can find applying Pythagorean theorem, as follows:

Replacing by the values in (1) we have:

which is equal to the option d).