Answer:
B. over the symbol.
Explanation:
vectors are represented with a symbol carrying an arrow head with also indicates direction
Answer:
When an object moves in a straight line with a constant acceleration, you can calculate its acceleration if you know how much its velocity changes and how long this takes.
The formula is,
Acceleration = change in velocity / time taken
The equation for acceleration can also be represented as:
a = (v-u) \ t
The change in velocity v – u = 5 – 0 = 5 m/s.
The acceleration = change in velocity ÷ time = 5 m/s ÷ 2 s = 2.5 m/s^2
The correct answer is A.
The coefficient of absorption of material A is 30%. So, the material will absorb 30% energy of the incident wave falling on it. Thus, the reflected wave will carry the rest 70% energy.
The coefficient of absorption of material B is 47%. So, the material will absorb 47% energy of the incident wave falling on it. Thus, the reflected wave will carry the rest 53% energy.
The coefficient of absorption of material C is 62%. So, the material will absorb 62% energy of the incident wave falling on it. Thus, the reflected wave will carry the rest 28% energy.
Hence, material C would be the best, because the percentage of the energy in an incident wave that remains in a reflected wave from this material is the smallest.