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."
Answer: 0.8 m
Explanation:
In the vertical direction, the speed is zero, u = 0.
Distance covered in the vertical direction, s = 0.75 m.
The book would fall with acceleration due to gravity in the vertical direction, a = g = 9.8 m/s²
From the equation of motion,
s = u t + 0.5 a t²
Substituting the above values, we will find out the time taken for the book to hit the ground.
⇒0.75 m=0+0.5×9.8 m/s²×t²
⇒t = √0.153 = 0.39 s ≈ 0.40 s
Now, the horizontal distance covered,
d = v×t ⇒d= 2.0 m/s × 0.40 s =0.8 m
Hence, the book falls 0.8 m away from the desk.
Answer:
1609.1429 rad/sec
Explanation:
By using the relation Angular velocity and frequency as:
Angular velocity (ω) = 2×π×Frequency (ν)
Given the frequency = 256 vibrations per second.
So, Angular velocity can be calculated by using the above formula as:
Angular velocity (ω) = 2×π×Frequency (ν)
⇒Angular velocity (ω) = 2×π×256 rad/ sec
⇒Angular velocity (ω) = 2×(22/7)×256 rad/ sec
<u>⇒Angular velocity (ω) = 1609.1429 rad/ sec</u>
Answer:
The mass of coal is 108 kg.
Explanation:
Given that,
Energy of coal = 1200 kg
Mass of aluminum = 1.0 kg
Energy required for single soda can = 15 g of Al
Energy required for 6 pack of cans = 
We need to calculate the mass of coal
Using formula of mass
Put the value into the formula
Put the value into the formula
Hence, The mass of coal is 108 kg.
Answer: Magnitude of electric field = 6.77×10^11N/C
Explanation: Electric field= E =KQ/ r ^2
Given:
Total charge Q=53.2nc
Radius 84cm= 0.84m
Coulombs constant K= 8.987x10^9NmC^-1
E =(( 8.987×10^9) × 53.2) /(0.84^2)
E = ( 4 . 777 ×10 ^ 9 )/ 0.7056
E = 6.77 × 10^ 11 NC^-1
