Answer:
u = - 20 cm
m =
Given:
Radius of curvature, R = 10 cm
image distance, v = 4 cm
Solution:
Focal length of the convex mirror, f:
f = 
Using Lens' maker formula:

Substitute the given values in the above formula:


u = - 20 cm
where
u = object distance
Now, magnification is the ratio of image distance to the object distance:
magnification, m =
magnification, m =
m =
m =
Yes yes it will............
Answer:
%
Explanation:
We have given cooler temperature that is
= 6°C =273+6=279 K
And the warm temperature of water that is 
The maximum possible efficiency is given by 
So maximum efficiency
%
Answer:
44.1 m
Explanation:
<u>Given:</u>
= speed of sound in air = 343 m/s
= speed of sound in the rod = 
= times interval between the hearing the sound twice = 0.12 s
<u>Assumptions:</u>
= length of the rod
= time taken by the sound to travel through the rod
= time taken by the sound to travel to through air to the same point = 
We know that the distance traveled by the sound in a particular medium is equal to the product of the speed of sound in that medium and the time taken.
For traveling sound through the rod, we have
..........eqn(1)
For traveling sound through the air to the women ear for traveling the same distance, we have

Hence, the length of the rod is 44.1 m.