# Search

astrophysics (85)biophysics (18)chemistry (23)electric field (70)electric current (75)gravitational field (80)hydromechanics (146)nuclear physics (44)oscillations (56)quantum physics (31)magnetic field (43)mathematics (89)mechanics of a point mass (295)gas mechanics (87)mechanics of rigid bodies (220)molecular physics (71)geometrical optics (77)wave optics (65)other (165)relativistic physics (37)statistical physics (21)thermodynamics (153)wave mechanics (51)

## electric current

### 2. Series 9. Year - E. afternoon tea

Establish the resistance of electric spiral boiler

**Hint:** Warm up water and measure the evolution of its temperature in time.

### 1. Series 9. Year - 3. plate capacitor

A capacitor formed by two parallel metal plates of area $S$ each placed in a distance $l_{1}$ one from another are charged at the voltage $U_{b}$. What work must be performed to move the plates apart to distance $l_{2}$, if we

- had disconnected,
- hadn’t disconnected

the battery..