Answer:
Explanation:
Diffraction grating is used to form interference pattern of dark and bright band.
Distance between adjacent slits (a ) = 1 / 420 mm
= 2.38 x 10⁻³ mm
2.38 x 10⁻⁶ m
wave length of red light
= 680 x 10⁻⁹ m
For bright red band
position x on the screen
= n λD / a , n = 0,1,2,3 etc
D = distance of screen
putting n = 1 , 2 and 3 , we can get three locations of bright red band.
x₁ = λD / a
= 680 x 10⁻⁹ x 2.8 / 2.38 x 10⁻⁶
= .8 m
= 80 cm
Position of second bright band
= 2 λD / a
= 2 x 80
= 160 cm
Position of third bright band
= 3 λD / a
= 3 x 80
= 240 cm
Answer:
Explanation:
There are several differences between a physical and chemical change in matter or substances. A physical change in a substance doesn't change what the substance is. In a chemical change where there is a chemical reaction, a new substance is formed and energy is either given off or absorbed.
Answer: Elastic Potential Energy
Explanation: Energy present on compressed strings is called Elastic Potential Energy.
Organisms that existed over a limited period
Explanation:
Index fossils are organisms that existed within a limited period in the geologic record.
These fossils are indicator fossils that serves as guide to define the relative ages of rocks in a sequence.
Here are some characteristics of index fossils:
- they must have existed over a limited period in their history.
- they must be very distinctive with short evolutionary tend.
- they must be abundant and highly widespread in the stratigraphic column.
Learn more:
Fossils brainly.com/question/7382392
#learnwithBrainly
Answer:
A 35 m/s
Explanation:
Speed of any object is scalar quantity while velocity is a vector. The scalar quantity is represented only by magnitude it doesn't need direction.
Hence, option A is correct as all other options have direction as well.
