The distance between the two cities is 513.24 km.
<h3>Time of motion when the two trains meet</h3>
The time spent on the journey when the two trains meet is calculated as follows;
(Va - Vb)t = d
where;
- d is the distance between the trains before meeting
(76 - 65)t = 40
11t = 40
t = 40/11
t = 3.64 hr
<h3>Distance traveled by the fast train</h3>
d1 = 76 km/h x 3.64 h
d1 = 276.64 km
<h3>Distance traveled by the slow train</h3>
d2 = 65 km/h x 3.64 h
d2 = 236.6 km
The distance between the two cities = 276.64 km + 236.6 km
= 513.24 km
Learn more about relative velocity here: brainly.com/question/17228388
It should be electromagnetic force
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:

Explanation:
Here we know that the EMF induced in this Field is given as

here B = perpendicular component of magnetic field
v = speed of the bird
L = length of the wings
now we have



now we have


13.6) When any boat displaces a weight of water equal to its own weight, it floats.