Answer:
3.76 m/s
Explanation:
Instantaneous velocity: This can be defined as the velocity of an object in a non uniform motion. The S.I unit is m/s.
v' = dx(t)/dt..................... Equation 1
Where v' = instantaneous velocity, x = distance, t = time.
Given the expression,
x(t) = 28.0 m + (12.4 m/s)t - (0.0450 m/s³)t³
x(t) = 28 + 12.4t - 0.0450t³
Differentiating x(t) with respect to t.
dx(t)/dt = 12.4 - 0.135t²
dx(t)/dt = 12.4 - 0.135t²
When t = 8.00 s.
dx(t)/dt = 12.4 - 0.135(8)²
dx(t)/dt = 12.4 - 8.64
dx(t)/dt = 3.76 m/s.
Therefore,
v' = 3.76 m/s.
Hence, the instantaneous velocity = 3.76 m/s
Answer:
1.4 m
Explanation:
v = Speed of sound in water = 1400 m/s
f = Frequency of sound = 1000 Hz
= Wavelength
When we multiply the frequency and the wavelength of a wave we get the velocity of sound in that medium

The wavelength of the sound waves in water is 1.4 m
Answer:
No, it is not proper to use an infinitely long cylinder model when finding the temperatures near the bottom or top surfaces of a cylinder.
Explanation:
A cylinder is said to be infinitely long when is of a sufficient length. Also, when the diameter of the cylinder is relatively small compared to the length, it is called infinitely long cylinder.
Cylindrical rods can also be treated as infinitely long when dealing with heat transfers at locations far from the top or bottom surfaces. However, it not proper to treat the cylinder as being infinitely long when:
* When the diameter and length are comparable (i.e have the same measurement)
When finding the temperatures near the bottom or top of a cylinder, it is NOT PROPER TO USE AN INFINITELY LONG CYLINDER because heat transfer at those locations can be two-dimensional.
Therefore, the answer to the question is NO, since it is not proper to use an infinitely long cylinder when finding temperatures near the bottom or top of a cylinder.
<u>Answer:</u>
0.24 m
<u>Explanation:</u>
Given:
Wave velocity ( v ) = 360 m / sec
Frequency ( f ) = 1500 Hz
We have to calculate wavelength ( λ ):
We know:
v = λ / t [ f = 1 / t ]
v = λ f
= > λ = v / f
Putting values here we get:
= > λ = 360 / 1500 m
= > λ = 36 / 150 m
= > λ = 0.24 m
Hence, wavelength of sound is 0.24 m.