Yes. a physical change is only modifying the structure of it.
a chemical change is permanently changing something.
cutting cheese into slices is a physical change
cooking an egg is a chemical change
It must have a medium. It must travel in empty space. Mechanical waves are waves which needs medium of propogation.
Answer:
the last one, It moves away from a mid-ocean ridge.
If the resistor is in series with the rest of the circuit then a is the correct answer. The voltage across the resistor in series with another resistor is

where R is the big resistor and r is the small one and V is the total voltage drop across both. This is called a voltage divider
Answer:
2.8 cm
Explanation:
= Separation between two first order diffraction minima = 1.4 cm
D = Distance of screen = 1.2 m
m = Order
Fringe width is given by

Fringe width is also given by

For second order

Distance between two second order minima is given by


The distance between the two second order minima is 2.8 cm