Answer:
dt/dx = -0.373702
dt/dy = -1.121107
Explanation:
Given data
T(x, y) = 54/(7 + x² + y²)
to find out
rate of change of temperature with respect to distance
solution
we know function
T(x, y) = 54 /( 7 + x² + y²)
so derivative it x and y direction i.e
dt/dx = -54× 2x / (7 +x² + y²)² .........................1
dt/dy = -54× 2y / (7 + x² + y²)² .........................2
now put the value point (1,3) as x = 1 and y = 3 in equation 1 and 2
dt/dx = -54× 2(1) / (7 +(1)² + (3)²)²
dt/dx = -0.373702
and
dt/dy = -54× 2(3) / (7 + (1)² + (3)²)²
dt/dy = -1.121107
Answer:
Upward force on the boy will be 1024 N
Explanation:
We have given mass of the boy m = 80 kg
Acceleration due to gravity 
It is given that elevator is ascending with acceleration of 
So net acceleration on the boy = 9.8+3 = 12.8
( As the car elevator is moving ascending )
So upward force on the boy will be equal to F = m(g+a)
So 
So upward force on the boy will be 1024 N
Answer:
They are both correct.
Explanation:
The density of an object is defined as the ratio of its mass to its volume. This implies that the density of the object is both proportional to the mass and also to the volume of the object. John only mentioned mass which is correct. Linda mentioned the second variable on which density depends which is the volume of the object.
Hence considering the both statements objectively, one can say that they are both correct.
The loudness of the sound at the rock concert, where the intensity of the sound is1 x 10⁻¹ Wm⁻² is 110 dB.
Here we are dealing with loudness which is the perception of the Intensity of the sound.
The formula to refer to in order to find the value of the loudness of a sound is ,
db= 10log(I/I₀)
As we are provided with the current intensity which is 1 x 10⁻¹ Wm⁻². and the initial intensity which is 1 x 10⁻¹² Wm⁻².
So, by substituting the required values in the formula we get
db= 10 * log( 1 x 10⁻¹ /1 x 10⁻¹²)
= 10 * 11 log(10)
= 110
So, the result is 110 dB.
To know more about the intensity of sound refer to the link brainly.com/question/9323731?referrer=searchResults.
To know more about questions related to loudness refer to the link brainly.com/question/21094511?referrer=searchResults.
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Answer: A.AB
Explanation:
This Velocity vs Time graph shows the acceleration of a body or object, since acceleration is the variation of velocity in time.
As we can see in the attached image, the graph can be divided in four segments:
OA: In this segment the acceleration is changing at a uniform rate. In addition we can see it has a positive slope, hence we are dealing with a positive uniform acceleration.
AB: In this segment the acceleration is changing at a nonuniform rate, since in this part it is not possible to calculate the slope. However if this were uniform, the slope woul be positive. This means the <u>acceleration is nonuniform and positive.</u>
BC: In this segment the acceleration is changing at a nonuniform rate, since in this part it is not possible to calculate the slope. However if this were uniform, the slope woul be negative. This means the acceleration is nonuniform and negative.
CD: In this segment the acceleration is changing at a uniform rate. In addition we can see it has a negative slope, hence we are dealing with a negative uniform acceleration.
From all these segments, the only one that fulfils the nonuniform positive acceleration condition is option A:
Segment AB