Out of the choices given, the statement about how light travels is "<span>Light can travel in a vacuum, and it travels faster if the light source is moving."</span>
Newtons 3.law: Action = Reaction
If a body exerts a force on a rope of 400 N the rope exerts a force on the body of 400N also. So the tension in the rope is 400N. See pictures below.
<span>D is at rest at the top of a 2 m high slope. The sled has a mass of 45 kg. The sled's potential energy is J?
</span>Answer: The sled's potential energy is 882 Joules
Answer: 430 nm.
Explanation:
The relation of wavelength and frequency is:
Formula used :
where,
= frequency =![6.88\times 10^{14}Hz](https://tex.z-dn.net/?f=6.88%5Ctimes%2010%5E%7B14%7DHz)
= wavelength = ?
c = speed of light = ![3.00\times 10^{8}m/s](https://tex.z-dn.net/?f=3.00%5Ctimes%2010%5E%7B8%7Dm%2Fs)
Now put all the given values in this formula, we get
![(1nm=10^{-9}m)](https://tex.z-dn.net/?f=%281nm%3D10%5E%7B-9%7Dm%29)
Thus the wavelength (in nm) of the blue light emitted by a mercury lamp is 430 nm.
Answer:
v = 282.84 m / s
Explanation:
The speed of a wave in a wire is given by the equation
.v = √ T /ρ
Where v is the speed of the wave, T the tension in the wire and ρ the density of the wire
If the tension is doubled
T = 2T₀
v = √ (2T₀ / ρ)
v = √2 √ T₀ / ρ
v = √2 v₀
calculate
v = √2 200
v = 282.84 m / s