Answer:
Option B: change the objective lens
Explanation:
The revolving nosepiece is one of the parts of a microscope. Its responsibility is to hold the objective lenses.
Answer:
They come in different kinds, called elements, but each atom shares certain characteristics in common. All atoms have a dense central core called the atomic nucleus. ... All atoms have at least one proton in their core, and the number of protons determines which kind of element an atom is.
Answer:
A hypothesis is an idea or explanation that you then test through study and experimentation.
Answer:
B) momentum and mechanical energy
Explanation:
In classical physics, a closed system is a system that does not exchange any matter with the surrounding, and on which there are no external forces acting on it.
Due to this definition, we have the following consequences:
- In a collision in a closed system, momentum is always conserved. This is because there is exchange of matter with the surroundings (so, no mass can be lost), and also because there are no external forces acting on the objects inside the system. In fact, the variation of the total momentum of the system is related to the net force acting on the system:
but since the net force F is zero, then the variation of momentum, , is also zero, therefore the momentum is constant.
- Also, mechanical energy is conserved. Mechanical energy is the sum of potential energy and kinetic energy of the system: again, since there are no external forces acting on the system, energy cannot be dissipated, so the total energy of the system cannot change.
Answer:
d = v² / (2μ g)
Explanation:
In the work relationship is equal to the variation of energy,
W = ΔEm
The work is defined by
W = F. d = F d cos θ
In this case the outside is the force of friction, which always opposes
to the movement, so the angle is 180 °
W = - fr d
The force of friction can be found with Newton's second law
fr = μ N
Y Axis
N- W = 0
N = mg
fr = μ m g
We substitute in the expression of work
W = - μ mg d
Now we use the relationship of work and energy
-μ mg d = 0 -½ m v²
d = v² / (2μ g)