Answer:
It's really important waves type for fulfill human's needs
Explanation:
Electromagnetic waves are transverse waves composed by the perpendicular oscillating electric and magnetic fields.
EM waves have both Electrical and magnetic features.
they travel in the velocity of light (3*10⁸ ms⁻¹)
they does not require any media to travel. It has two perpendicular electric field and the magnetic field which are perpendicular to each other
They travel perpendicular to each of those electric and magnetic fields.
Example :
- Radio Wave
- Micro Wave
- IR wave
- Light Wave
- UV rays
- X rays
- Gamma rays
- Cosmic rays
The main importance of em waves is they allow energy to be stored within them and then can be propagated over a large distance using the dielectric and magnetic properties of materials .
This performance has been used in many fields wisely and effectively to make the things easy.
Ex : medicine , Telecommunication , energy , Engineering etc
I believe the answer is stored energy.
Answer: Friction is the resistance to motion of one object moving relative to another. For example, when you try to push a book along the floor, friction makes this difficult. Force: Force is essentially a push, or a pull action, that can lead to certain outcomes.
Answer
given,
Side of copper plate, L = 55 cm
Electric field, E = 82 kN/C
a) Charge density,σ = ?
using expression of charge density
σ = E x ε₀
ε₀ is Permittivity of free space = 8.85 x 10⁻¹² C²/Nm²
now,
σ = 82 x 10³ x 8.85 x 10⁻¹²
σ = 725.7 x 10⁻⁹ C/m²
σ = 725.7 nC/m²
change density on the plates are 725.7 nC/m² and -725.7 nC/m²
b) Total change on each faces
Q = σ A
Q = 725.7 x 10⁻⁹ x 0.55²
Q = 219.52 nC
Hence, charges on the faces of the plate are 219.52 nC and -219.52 nC
Answer:
A. cell walls
Explanation:
Plants have cell walls but animals dont.
