Answer:
One simple explanation is that planets move, while stars remained fixed in the sky. You can observe a planet's orbit, but a star will stay in the same position.
Explanation:
If we have a vector P, then we name it's components by the axis we project it onto.
In 2D Cartesian coordinate system we have one x axis and one y axis.
Vector P can then be represented with two components: Px and Py.
Px is the component of vector P on the x axis and Py is the component of the vector P on the y axis.
Answer:
Explanation:
For third normal mode of vibration
l = 
, λ is wavelength , l is length of string .
.4 =
λ = .267 m
velocity = 
T is tension and m is mass unit length
m = .5 x 10⁻³ / 40 x 10⁻²
= .00125 kg / m
Putting the values
velocity = 
= 253 m /s
frequency
= velocity / λ
= 253 / .267
= 947.5 Hz .
