The answer is true
It wouldn’t be false, it wouldn’t make any sense for it to be false
Answer:
All the given options will result in an induced emf in the loop.
Explanation:
The induced emf in a conductor is directly proportional to the rate of change of flux.
where;
A is the area of the loop
B is the strength of the magnetic field
θ is the angle between the loop and the magnetic field
<em>Considering option </em><em>A</em>, moving the loop outside the magnetic field will change the strength of the magnetic field and consequently result in an induced emf.
<em>Considering option </em><em>B</em>, a change in diameter of the loop, will cause a change in the magnetic flux and in turn result in an induced emf.
Option C has a similar effect with option A, thus both will result in an induced emf.
Finally, <em>considering option</em> D, spinning the loop such that its axis does not consistently line up with the magnetic field direction will<em> </em>change the angle<em> </em>between the loop and the magnetic field. This effect will also result in an induced emf.
Therefore, all the given options will result in an induced emf in the loop.
The weight of the needle is 0.007 N.
Explanation:
Surface tension is the force acting on the surface of any fluid or film due to the attractive forces on the surface of them. So it is measured as force acting per unit effective length on the surface. The effective length is the distance or the length which is in contact with the surface.
For example, in the present case, the needle can be in contact with the water body from both sides of the needle. So effective length of the needle will be 2 times the length of the needle. Then the surface tension on the water due to the needle will be
As the length of the needle is given as 5 cm = 0.05 m and the surface tension of water is given as 0.07 N/m, then the weight of the needle will be equal to the force applied by the needle.
So, the weight of the needle is 0.007 N.
Answer:
i) Telescopes can be used to view far distant objects but the human eye can't view far distant objects.
ii) Telescopes uses two convex lenses producing a magnified image while the human eye only possesses one convex lens (image seen are smaller than that viewed under telescopes)
Explanation:
The telescopes can be used to view far distant objects due to their presence of two convex lenses. The two convex lenses are the objective lens (lens closer to object) and the eye piece lens (lens closer to eye). The object to be viewed forms an intermediate image first before the final image is seen using the eye piece lens.
The human eye only possess one convex lens and as such cannot view far ranged objects.