Answer:
f = 409 Hz
Explanation:
We have,
Length of the open organ pipe, l = 0.29 m
Frequency of vibration of second overtone, 
It is required to find the fundamental frequency of the pipe. For the open organ pipe, the frequency of second overtone is given by :

v is speed of sound
Let f is the fundamental frequency. It is given by :

The relation between f and f₂ can be written as :

So, the fundamental frequency of the pipe is 409 Hz.
Answer:
Part a)

Part b)

Explanation:
Resistance of the solenoid is given as
R = 4.10 ohm
now we have

here we know that



now from above formula


Part a)
now we know that it is wounded over the solenoid
so here we can say



Part b)
now length of solenoid is given as



Answer: "For a projectile with no air resistance, at the peak of its path, it's velocity is equal to zero"
Explanation:
Suppose that you throw an object up. The initial vertical velocity will be positive, and the acceleration (the gravitational acceleration) will point downwards, meaning that it opposes to the initial direction of the velocity, and that decreases the velocity as the time goes by.
There will be a point where the velocity ( that was positive until now, so until now the height of the object was increasing), is equal to zero, this means that at this moment the object stops moving, and after, because we still have negative acceleration, the velocity will start become negative, and the object will fall down.
Then that point where the velocity was zero is the peak of its path, then we can conclude that:
"For a projectile with no air resistance, at the peak of its path, it's velocity is equal to zero"
V ( initial ) = 20 m/s
h = 2.30 m
h = v y * t + g t ² / 2
d = v x * t
1 ) At α = 18°:
v y = 20 * sin 18° = 6.18 m/s
v x = 20 * cos 18° = 19.02 m/ s
2.30 = 6.18 t + 4.9 t²
4.9 t² + 6.18 t - 2.30 = 0
After solving the quadratic equation ( a = 4.9, b = 6.18, c = - 2.3 ):
t 1/2 = (- 6.18 +/- √( 6.18² - 4 * 4.9 * (-2.3)) ) / ( 2 * 4.9 )
t = 0.3 s
d 1 = 19.02 m/s * 0.3 s = 5.706 m
2 ) At α = 8°:
v y = 20* sin 8° = 2.78 m/s
v x = 20* cos 8° = 19.81 m/s
2.3 = 2.78 t + 4.9 t²
4.9 t² + 2.78 t - 2.3 = 0
t = 0.46 s
d 2 = 19.81 * 0.46 = 9.113 m
The distance is:
d 2 - d 1 = 9.113 m - 5.706 m = 3.407 m
Answer:
The time taken by the car to accelerate from a speed of 24.6 m/s to a speed of 26.8 m/s is 0.84 seconds.
Explanation:
Given that,
Acceleration of the car, 
Initial speed of the car, u = 24.6 m/s
Final speed of the car, v = 26.8 m/s
We need to find the time taken by the car to accelerate from a speed of 24.6 m/s to a speed of 26.8 m/s. The acceleration of an object is given by :


t = 0.84 seconds
So, the time taken by the car to accelerate from a speed of 24.6 m/s to a speed of 26.8 m/s is 0.84 seconds. Hence, this is the required solution.