Concept: The magnification of spherical mirror can be defined by two ways.
(i) In terms of the height of the object and image.
The magnification of the spherical mirror is defined as the ratio of the height of the image'
' to the height of the object '
'. It is denoted by letter 'm'.
Mathematically, it can be written as
(ii) In terms of the object's and image's distances.
The magnification of the spherical mirror is defined as the negative ratio of the image distance'
' to the object distance '
'.
Mathematically, it can be written as
Now, from equation (1) and (2) we have,
Given: Spherical Concave Mirror,
We will consider positive sign for object's and image's distance because both are in front of the mirror.
Object distance 
.
Image distance 
Object's height 
Image's height 
Now, apply equation (3)
Or, hi = - 8 mm
Here; negative sign means, the image will be inverted.
The image's height will be 8 mm.
Answer:
Explanation:
Total momentum of the system before the collision
.5 x 3 - 1.5 x 1.5 = -0.75 kg m/s towards the left
If v be the velocity of the stuck pucks
momentum after the collision = 2 v
Applying conservation of momentum
2 v = - .75
v = - .375 m /s
Let after the collision v be the velocity of .5 kg puck
total momentum after the collision
.5 v + 1.5 x .231 = .5v +.3465
Applying conservation of momentum law
.5 v +.3465 = - .75
v = - 2.193 m/s
2 ) To verify whether the collision is elastic or not , we verify whether the kinetic energy is conserved or not.
Kinetic energy before the collision
= 2.25 + 1.6875
=3.9375 J
kinetic energy after the collision
= .04 + 1.2 =1.24 J
So kinetic energy is not conserved . Hence collision is not elastic.
3 ) Change in the momentum of .5 kg
1.5 - (-1.0965 )
= 2.5965
Average force applied = change in momentum / time
= 2.5965 / 25 x 10⁻³
= 103.86 N
The process of changing from one phase of matter to another is a physical matter.
Answer:
During convection, hot material expands & rises then moves to the side and cools & sinks. this circular pattern is called a convection current.
Explanation:
Convection is one of the three methods of transfer of heat. It occurs only in fluids (liquids or gases).
Convection occurs when there is a source of heat that heats a fluid, such as in a boiling pot of water. The water which is on the bottom of the pot becomes warmer before than the water at the top (because it is closer to the flame), and so it becomes less dense: for this reason, it expands and it becomes rising. On the contrary, the water on top is colder, so it is more dense and starts sinking, replacing the warmer water. As the new part of water gets warmer, it starts rising, and so the process is continuously repeated. This circular current is called convection current.
