Answer:
Explanation:
magnetic field due to circular wire
= μ₀ i / 2r
i is current and r is radius of coil .
Magnetic fields due to inner coil
μ₀ x 20 / (2 x 9.5 x 10⁻²)
Magnetic field due to outer coil
= μ₀ x I / (2 x 19 x 10⁻²) , I is the current to be calculated
Total field
μ₀ x 20 /( 2 x 9.5 x 10⁻²) +μ₀ x I / (2 x 19 x 10⁻²) = 0
20 + I /2 = 0
I = - 40 A
Current required is 40 A , and it will be in opposite direction.
Answer - B. Betelguese.
I really hope this helps!!
is the intensity of the sound.
Answer: Option B
<u>Explanation:</u>
The range of sound intensity that people can recognize is so large (including 13 magnitude levels). The intensity of the weakest audible noise is called the hearing threshold. (intensity about
). Because it is difficult to imagine numbers in such a large range, it is advisable to use a scale from 0 to 100.
This is the goal of the decibel scale (dB). Because logarithm has the property of recording a large number and returning a small number, the dB scale is based on a logarithmic scale. The scale is defined so that the hearing threshold has intensity level of sound as 0.

Where,
I = Intensity of the sound produced
= Standard Intensity of sound of 60 decibels = 
So for 19 decibels, determine I as follows,



When log goes to other side, express in 10 to the power of that side value,


Answer:
The inner planets are smaller and rockier
Explanation:
Astronomers divide the planets into two groups in Solar system, the inner planets and outer planets. The inner planets are smaller and rockier and it is closer to the sun. The outer planets are larger , further far away and made of gas
The inner planets are Mercury, Venus , Earth and Mars. The outer planets Jupiter , Saturn , Uranus and Neptune comes after an asteroid belt. In some other planetary systems the gas are close to the sun.
particles in a disk of gas and dust will form Planets. If they orbit the star they are colliding and sticking. The stars wind blows away their gases . So the nearest planets to starts are rockier.