Answer:
90x20=1800
Explanation:
just multiply 10 & 9 and then mutiply 90x20 or 20x90
Light. The black hole is a vacuum, and not even light can escape it's suction
Explanation:
Given that,
Object distance u= -110 cm
Image distance v= 55 cm
We need to calculate the focal length for diverging lens
Using formula of lens
Put the value into the formula
The focal length of the diverging lens is 36.6 cm.
Now given a thin lens with same magnitude of focal length 36.6 cm is replaced.
Here, The object distance is again the same.
We need to calculate the image distance for converging lens
Using formula of lens
Here, focal length is positive for converging lens
The distance of the image is 54.85 cm from converging lens.
Hence, This is the required solution.
Answer:
She run for, t = 0.92 s
Explanation:
Given data,
The velocity of the runner, v = 10 km/h
The distance covered by the runner, d = 9.2 km
The relationship between the velocity, displacement and time is given by the formula,
t = d / v
Substituting the given values in the above equation,
t = 9.2 / 10
= 0.92 s
Hence, she ran for, t = 0.92 s
The speed of light to be slightly less in atmosphere then in vacuum because of absorption and re-emission of light by the atmospheric molecules occurred when light travels through a material
<u>Explanation:</u>
When light passes through atmosphere, it interacts or transmits through the transparent molecules in atmosphere. In this process of transmission through atmosphere, the light will be getting absorbed by them and some will get re-emitted or refracted depending upon wavelength.
But in vacuum the absence of any kind of particles will lead to no interaction and no energy loss, thus the speed of the light will be same in vacuum while due to interactions with molecules of atmosphere, there speed will be slightly less compared to in vacuum.
