No, she has it backward. Waves interfere with each other and reflect off objects. When two waves overlap their amplitudes add. If they have the same sign this addition is constructive, meaning the amplitudes grow. If they have opposite signs this constitutes subtraction and the waves can partially, or completely cancel. This is known as interference. Reflection occurs when waves travel from one medium to another. If the wave impedance of the new medium is different (which it generally is) there will be a partial, or even total, reflection.
Answer: Option (b) is the correct answer.
Explanation:
As Kristina is over training, therefore, there is pain in her muscles because human body also requires rest in order to work or function properly.
That is why, gym trainers suggest to give one day off in a week for your workout sessions so that body muscles should recover.
Thus, we can conclude that if Kristina is over training, then recovery training principle should Kristina consider before continuing her program.
Let 
be the direction the swimmer must swim relative to east. Then her velocity relative to the water is
The current has velocity vector (relative to the Earth)
The swimmer's resultant velocity (her velocity relative to the Earth) is then
We want the resultant vector to be pointing straight north, which means its horizontal component must be 0:
which is approximately 41º west of north.
Answer:
why should we do , do by your own , no sense
Explanation:
Answer:
a) 447.21m
b) -62.99 m/s
c)94.17 m/s
Explanation:
This situation we can divide in 2 parts:
⇒ Vertical : y =-200 m
y =1/2 at²
-200 = 1/2 *(-9.81)*t²
t= 6.388766 s
⇒Horizontal: Vx = Δx/Δt
Δx = 70 * 6.388766 = 447.21 m
b) ⇒ Horizontal
Vx = Δx/Δt ⇒ 70 = 400 /Δt
Δt= 5.7142857 s
⇒ Vertical:
y = v0t + 1/2 at²
-200 = v(5.7142857) + 1/2 *(-9.81) * 5.7142857²
v0= -7 m/s ⇒ it's negative because it goes down.
v= v0 +at
v= -7 + (-9.81) * 5.7142857
v= -62.99 m/s
c) √(70² + 62.99²) = 94.17 m/s
