Coulombs law says that the force between any two charges depends on the amount of charges and distance between them. This force is directly proportional to the magnitude of the two charges and inversely proportional to the distance between them.

where
are charges,
is the distance between them and k is the coulomb constant.
case 1:

case 2

case 3:

Comparing the 3 cases:
The maximum potential force according to coulombs law is between -1 charge and +3 charge separated by a distance of 100 pm.
Answer:
3. both are true.
Explanation:
Energy increses with decrease in wavelenght.
For photoemission to occur, a threshold energy barrier must be broken.
Higher energy means more electrons will be emmited.
The electrons emmited will posses energy that is less than the incident energy by the value of the threshold energy.
So the higher the energy, the higher the energy possessed by the electrons.
Answer:
the value of acceleration as a body moves with an uniform speed is zero
Answer:
In two significant figure 360K
Explanation:
The temperature difference (ΔT) can be calculated as the boiling temperature minus the freezing temperature in Fahrenheit.
Hence,
ΔT = 212 - 32
ΔT = 180°F
To convert to °F to kelvin, we use the formula below
= (°F - 32) × 5/9 + 273.15
= (180°F - 32) × 5/9 + 273.15
= 355.37K ⇔ 360K
Answer:
The distance between the two objects must be squared.
Explanation:
Gravitational force always act between two objects that have mass. The gravitational force is a weak force and attractive in nature.
The force of pull depends on the masses of the two objects and the distance between them.
The formula to calculate gravitational force between two objects having masses 'm' and 'M' and separated by a distance 'd' is given as:

Where, 'G' is called the universal gravitational constant and its value is equal to
.
Now, from the above formula, it is clear that, the force of gravitation is inversely proportional to the square of the distance between the two objects.
Thus, the quantity that must be squared in the equation of gravitational force between two objects is the distance 'd'.