Can anyone say this is from which book And can you solve these question

A certain microwave has a

Tatiana [17]

Answer:

$9.375\times 10^{9} Hz$

Explanation:

Frequency is mathematically defined as the quotient of speed divided by wavelength.

$Frequency= \frac {v}{W}$

where

v-is the speed of light

-w is wavelength.

Given the speed of the wave as $V=300000000 \ m/s$ and the wavelength $\lambda= 0.032\ m$ , we substitute these values in the Frequency function to solve for frequency:

$Frequency=\frac {300000000}{0.032}=9375000000 Hz=9.375\times 10^{9} Hz$

Hence, the wave's frequency is $9.375\times 10^9\ Hz$

5 0

4 years ago

A wire carrying a 30.0-A current passes between the poles of a strong magnet that is perpendicular to its field and experiences

Zanzabum

Answer:

1.79 T

Explanation:

Applying,

F = BILsin∅................ Equation 1

Where F = Force, B = magnetic field, I = current flowing through the wire, L = length of the wire, ∅ = angle between the magntic field and the force

make B the subject of the equation

B = F/ILsin∅............. Equation 2

From the question,

Given: F = 2.15 N, I = 30 A, L = 4.00 cm = 0.04 m, ∅ = 90° (perpendicular to the field)

Substitute these values into equation 2

B = 2.15/(30×0.04×sin90°)

B = 2.15/1.2

B = 1.79 T

Hence the average field strength is 1.79 T

8 0

3 years ago

A shopper weighs 4.00 kg of apples on a supermarket scale whose spring obeys Hooke's law and notes that the spring stretches a d

Irina-Kira [14]

Answer:

a) 0.040625 m

b) 5.02272 J

Explanation:

k = Spring constant

x = Stretched length

F = Force

a)

$F=kx\\\Rightarrow k=\frac{F}{x}\\\Rightarrow k=\frac{4\times 9.81}{0.025}\\\Rightarrow k=1569.6\ N/m$

$F=kx\\\Rightarrow x=\frac{F}{k}\\\Rightarrow x=\frac{6.5\times 9.81}{1569.6}\\\Rightarrow x=0.040625\ m$

Extension of the spring would be 0.040625 m

b) Work done in a spring

$W=\frac{1}{2}kx^2\\\Rightarrow W=\frac{1}{2}\times 1569.6\times 0.08^2\\\Rightarrow W=5.02272\ J$

The work done by the shopper to stretch this spring a total distance of 8.00 cm is 5.02272 J

4 0

3 years ago

Assuming that the cost of 16-gauge steel sheet metal is $25.00 per square meter, what is the ideal radius and height of a cylind

Anton [14]

Answer: Radius = 32.7 cm and height = 65.5 cm

Explanation:

An oil drum must have a volume of 218 liters or 218*1000cm^3 = 218,000 cm^3

The price is per square meter, so if we reduce the surface of the oil drum, we will pay less:

So we want to play with the measures of the oil drum in such a way that the surface is minimized.

Now, first, the volume of the oil drum (a cylinder) is:

V = pi*r^2*h

where pi = 3.14, r is the radius and h is the height.

and the surface is:

S = 2*pi*r^2 + 2*pi*r*h

we know that:

pi*r^2*h = 218,000 cm^3

r^2*h = 218,000cm^3/3.14 = 70,096.5 cm^3

now we can write

h = 70,096.5 cm^3/r^2

now we can replace it in the surface equation:

S = 2*pi*r^2 + 2*pi*r*h

= 6.28*(r^2 + 70,096.5 cm^3/r)

So we want to minimize this, we can derivate it and find the zero:

S' = 6.28(2*r - 70,096.5 cm^3/r^2) = 0

2r = 70,096.5 cm^3/r^2

r^3 = (70,096.5 cm^3)/2

r = ∛( (70,096.5 cm^3)/2 ) = 32.7cm

And then the height is:

h = 70,096.5 cm^3/r^2 = 70,096.5 cm^3/(32.7cm)^2 = 65.5cm

4 0

3 years ago

Caroline, a piano tuner, suspects that a piano's B4 key is out of tune. Normally, she would play the key along with her B4 tunin

Sergeeva-Olga [200]

Answer:

455.9 Hz, Flat

Explanation:

The beat frequency is basically the difference between the frequency of the B4 note and the frequency of the A4 tuning fork. This means the B4 note is 15.9 Hz off of 440Hz, and 67.4 Hz off of 525.3 Hz. As B4 is between the two notes, it would make sense to find its frequency by adding 15.9 to 440 and subtracting 67.4 from 523.3, both if which give us a frequency 455.9 Hz for the B4 key. This is because the note doesn't change for the different turning forks so both differences should result in the same frequency. Because the note should be 493.9 frequency but instead has a frequency of 455.9 Hz, it is flat because the frequency is lower than it is supposed to be.

Hope this helped!

7 0

4 years ago