11m/s Bc of the fact that he sees her running at 11m/s
Answer:
No.
Explanation:
Electromagnetic waves do not require a medium of matter to move through, electromagnetic waves are used in things like your cell phone and telecommunications.
Answer:
d_{b} = 2 d_{a}
Explanation:
The electrical resistance for a cylindrical wire is described by the expression
R = ρ L / A
The area of a circle is
A = π r²
r = d / 2
A = π d²/4
We substitute
R = ρ L 4 /π d²
Let's apply this expression to our case, they indicate that the resistance of wire A is 4 times the resistance of wire B
= 4 R_{b}
We substitute
ρ 4/π
² = 4 (ρ 4/π d_{b}²)
1 / d_{a}² = 4 / d_{b}²
d_{a} = d_{b} / 2
Answer:
The principle of momentum conservation states that if there no external force the total momentum of the system before and after the collision is conserved.
Since momentum is a vector, we should investigate the directions and magnitudes of initial and final momentum.

If the first ball hits the second ball with an angle, we should separate the x- and y-components of the momentum (or velocity), and apply conservation of momentum separately on x- and y-directions.
Wave speed = (wavelength) x (frequency)
Wave speed = (3 m) x (15 Hz)
<em>Wave speed = 45 m/s</em>