When you rub inflated balloon with your hair or your kitten's fur, charge is induced on all over the balloon's surface. This is called "charging by friction" because you developed charges by rubbing to bodies with each other. It will also stick on your wall you can check it out. This is because of "unlike charges attract each other". Rubbed balloon and wall possessed unlike charges which made them stick together.
Electromagnets can be turned off, this makes it easier to release things from the magnetic field.
Hope this helps :)
True because all switches use contacts to start or stop the flow of electrons in a circuit
Answer:
a)
, b)
, c) 
Explanation:
a) The capacitance of two parallel plates capacitor with dielectric is given by the following expression:

Where:
- Dielectric constant.
- Vaccum permitivity.
- Plate area.
- Distance between plates.
Hence, the capacitance of the system is:



b) The charge can be found by using the definition of capacitance:




c) The energy stored in the charged capacitor is:




Answer:
Sample Response: In a vacuum, there are no atoms or particles that interfere with the path of light. However, in other media, the speed of light is lower than 3.0 × 108 m/s because the wave is continuously absorbed and re-emitted by each atom in its path. The differences in speed are due to the composition of the medium and the density of the particles in the medium.
Explanation: