Answer: final Displacement = 0 km, total distance covered =7 km
Explanation:
Given the following :
From home to library = 1.3 km East
Library to music store = 0.68km East
Music store to friend's house = 1.1km North
Friend's house to grocery store = 0.42 km North
Displacement is the net change in distance traveled.
Eastward distance :
To = (1.3 + 0.68)km = 1.98km East
Fro = (0.68 + 1.3)km = 1.98 km East
Δ distance = (1.98 - 1.98) = 0
Northward direction:
To = (1.1 + 0.42)km = 1.52km north
Fro = (0.42 + 1.1)km = 1.52km North
Δ distance = (1.98 - 1.98) = 0
Hence final Displacement = 0
Total distance covered = 2 × (1.3 + 0.68 + 1.1 + 0.42) = 2 × 3.5
= 7km
Answer: D. A wave with a shorter wavelength is always faster than one with a longer wavelength
Explanation: "Imagine two sets of waves that have the same speed. <u><em>If one set has a longer wavelength, it will have a lower frequency (more time between waves). If the other set has a shorter wavelength, it will have a higher frequency</em></u> (less time between waves). Light moves even faster AND has shorter wavelengths."
Why it's not C: "The number of complete wavelengths in a given unit of time is called frequency (f). <em><u>As a wavelength increases in size, its frequency and energy (E) decrease</u></em>. From these equations you may realize that as the frequency increases, the wavelength gets shorter. As the frequency decreases, the wavelength gets longer."
Why it's not B: "The frequency does not change as the sound wave moves from one medium to another. Since the speed changes and the frequency does not, the wavelength must change."
Why it's not A: "Do loud sounds travel faster than soft sounds? No. Both travel at the same speed The speed depends on the medium it passes through. Louder sounds are simply sound waves with higher amplitude traveling at the same speed."
<em>Another key factor that determines a star's colour is its temperature. As stars become hotter, the overall radiated energy increases, and the peak of the curve changes to shorter wavelengths. To put it another way, when a star heats up, the light it produces moves toward the blue end of the spectrum.</em>
