Answer:
350.72 m/s
Explanation:
Formula for velocity of wave is;
v = fλ
Where;
v is speed
f is frequency
λ is wavelength
We are given;
f = 512 Hz
λ = 0.685 m
Thus;
v = 512 × 0.685
v = 350.72 m/s
Solution:
With reference to Fig. 1
Let 'x' be the distance from the wall
Then for
DAC:

⇒ 
Now for the
BAC:

⇒ 
Now, differentiating w.r.t x:
![\frac{d\theta }{dx} = \frac{d}{dx}[tan^{-1} \frac{d + h}{x} - tan^{-1} \frac{d}{x}]](https://tex.z-dn.net/?f=%5Cfrac%7Bd%5Ctheta%20%7D%7Bdx%7D%20%3D%20%5Cfrac%7Bd%7D%7Bdx%7D%5Btan%5E%7B-1%7D%20%5Cfrac%7Bd%20%2B%20h%7D%7Bx%7D%20-%20%20tan%5E%7B-1%7D%20%5Cfrac%7Bd%7D%7Bx%7D%5D)
For maximum angle,
= 0
Now,
0 = [/tex]\frac{d}{dx}[tan^{-1} \frac{d + h}{x} - tan^{-1} \frac{d}{x}][/tex]
0 = 

After solving the above eqn, we get
x = 
The observer should stand at a distance equal to x = 
Answer:
The maximum height attained by the object and the number of seconds are 128 ft and 4 sec.
Explanation:
Given that,
Initial velocity u= 128 ft/sec
Equation of height
....(I)
(a). We need to calculate the maximum height
Firstly we need to calculate the time

From equation (I)




Now, for maximum height
Put the value of t in equation (I)


(b). The number of seconds it takes the object to hit the ground.
We know that, when the object reaches ground the height becomes zero




Hence, The maximum height attained by the object and the number of seconds are 128 ft and 4 sec.
Answer:
D. ) The force would be zero newtons
Explanation:
Because
If you are at the center of the earth, gravity is zero because all the mass around you is pulling "up" (every direction there is up!)
So F=mg so if g is zero F is also zero
Answer:
(a). The average speed is 51.83 m/s.
(b). The average velocity over one revolution is zero.
Explanation:
Given that,
Angular velocity = 110 rev/m
Radius = 4.50 m
(a). We need to calculate the average speed
Using formula of average speed



(b). The average velocity over one revolution is zero because the net displacement is zero in one revolution.
Hence, (a). The average speed is 51.83 m/s.
(b). The average velocity over one revolution is zero.