Answer: f = -12 cm
Explanation: <u>Combined</u> <u>lenses</u> is an array of simple lenses with a common axis. The combination is useful for correction of optical aberrations which cannot be corrected by simple lenses.
When two lenses are in contact and are thin, focal lengths are related as:
If there is a distance between the lenses, the focal length will be:
Since the lenses in the question above are thin and in contact, the focal length of one of them will be:
-12
The focal length of the other lens is -12 cm, with the negative sign meaning it's a converging lens.
Inertia
A bowling ball has a higher inertia than bowling pins, as it weighs significantly more than the pins.
Answer: depth = 3.75 m
Explanation:
Taken the speed of the sound in sea to be V = 1500 m/s
The time between an echo sounder sending and receiving a pulse is 0.005 s. That is,
Total time T = 0.005
Formula for echo is:
V = 2X/T
Where X = distance covered
Substitute V and T into the formula
1500 = 2X/0.005
Cross multiply
7.5 = 2X
Make X the subject of formula
X = 7.5/2
X = 3.75 m
Therefore, the depth of the sea is 3.75 m
Answer:
a. 
b. 
Explanation:
Using the triangle theorem both triangle the woman makes between the light so the rate of change of length can use geometry first
Solve to find the rate relation
Now the rate of the change rate
Finally the rate of her shadow moving
Answer:
The theory of relativity usually encompasses two interrelated theories by Albert Einstein: special relativity and general relativity, proposed and published in 1905 and 1915, respectively. Special relativity applies to all physical phenomena in the absence of gravity. General relativity explains the law of gravitation and its relation to other forces of nature.It applies to the cosmological and astrophysical realm, including astronomy.
The theory transformed theoretical physics and astronomy during the 20th century, superseding a 200-year-old theory of mechanics created primarily by Isaac Newton. It introduced concepts including spacetime as a unified entity of space and time, relativity of simultaneity, kinematic and gravitational time dilation, and length contraction. In the field of physics, relativity improved the science of elementary particles and their fundamental interactions, along with ushering in the nuclear age. With relativity, cosmology and astrophysics predicted extraordinary astronomical phenomena such as neutron stars, black holes, and gravitational waves
