If the angle is either 0 or 180, that means that there is either negative or positive work, so A and D are not correct.
If the angle is 45, then there is still some work involved.
The only option where there is no work done by a force is B. when the angle is between the force and displacement is 90.
proton is the name for a nuclear particle that has about the same mass as a neutron, but with a positive charge.
Since both atoms are the same and are both nonmetals, they would form a Nonpolar covalent bond. This bond occurs when usually atoms of the same element or atoms of propriety electronegativity differences are sharing electrons to form bonds. There is an equal sharing of valence electrons in this chemical bond.
Answer:
element
Explanation:
we know that helium is a pure substance although helium atoms are sometimes mixed with their isotopes it is still the same element. since there is no other element combined with helium this makes it an element.