Question

В однородном электрическом поле между горизонтальными пластинами в равновесии находится заряженная пыль массой 10^-6 г. Сколько лилий зарядит маслобойка, если расстояние между пластинами 4 см и напряжение 200 В?

Answer 1

Ответ:

Дано:

m=10^-11 кг.

U=500 В.

d=0,1 м.

q=?

_______

Решение:

т.к. сказано, что пылинка удерживается в равновесии, то сила тяжести равна электрической силе.

q - искомый заряд. E - напряженность поля, формула которой: 

Подставляем и считаем:

Считаем:

q=(10^-11*10*0,1)/500=2*10^-14 Кл.

Ответ: q=2*10^-14 Кл.

Answer 2

To calculate the charge on the oil droplet, we can use the formula for the electric field between parallel plates:

E = V/d

Where: - E is the electric field strength - V is the voltage between the plates - d is the distance between the plates

Given that the distance between the plates is 4 cm (or 0.04 m) and the voltage is 200 V, we can calculate the electric field strength:

E = 200 V / 0.04 m = 5000 V/m

Now, to find the charge on the oil droplet, we can use the formula for the force on a charged particle in an electric field:

F = qE

Where: - F is the force on the particle - q is the charge on the particle - E is the electric field strength

In this case, the force on the oil droplet is due to the gravitational force and the electric force. At equilibrium, these forces balance each other:

F_gravity = F_electric

The gravitational force can be calculated using the formula:

F_gravity = mg

Where: - F_gravity is the gravitational force - m is the mass of the oil droplet - g is the acceleration due to gravity (approximately 9.8 m/s^2)

Given that the mass of the oil droplet is 10^-6 g (or 10^-9 kg), we can calculate the gravitational force:

F_gravity = (10^-9 kg) * (9.8 m/s^2) = 9.8 * 10^-9 N

Since the gravitational force and the electric force are equal at equilibrium, we can equate the two:

F_gravity = F_electric

mg = qE

Solving for q, we get:

q = mg / E

Substituting the values we have:

q = (10^-9 kg) / (5000 V/m) = 2 * 10^-13 C

Therefore, the charge on the oil droplet is 2 * 10^-13 C.

Please note that this calculation assumes that the oil droplet is a point charge and neglects any other forces or effects that may be present in the system.