Answer:
At the focus
Explanation:
In car head lights concave mirrors are used. The light bulbs in these headlights are place along the principal axis as shown in the figure. On this Principal axis light bulbs are place at the Focus to get maximum brightness. As from the figure we can conclude that light rays coming from infinity converse at focus thus, giving maximum brightness.
it is from under the earth's surface. There are under the surface streams that create springs
It is precipitation that fell on the ground and seeped down to a layer of rock. The water comes from an aquifer that is under the ground.
Answer:
Induced emf, 
Explanation:
We have,
Number of turns in the coil, N = 40
Radius of coil, r = 3 cm = 0.03 m
The field increases from 0 to 0.75 T at a constant rate in a time interval of 225 s.
It is required to find the magnitude of the induced emf in the coil if the field is perpendicular to the plane of the coil. The induced emf is given by :
, is magnetic flux
So, the magnitude of induced emf is 
.
Lithium-Ion batteries are commonly used in portable electronics and electric vehicles. These rechargeable batteries have two electrodes: one that's positively charged and contains lithium and another negative one that's typically made of graphite.
Answer:
14 cm
Explanation:
Power of eye = 57.1 D
The relation between the focal length and the power is
f = 1 / P = 1 / 57.1 = 0.0175 m = 1.75 cm
The distance between the image and the lens is, v = 2 cm
Let the distance between the object and the eye is u
Use the lens equation
1/ f = 1 / v - 1 / u
1 / 1.75 = 1 / 2 - 1 / u
1 / u = 1 / 2 - 1 / 1.75
1 / u = (1.75 - 2) / 3.5
u = - 14 cm
Thus, the distance between the feature and eye is 14 cm .
