Answer:
Both require time, but velocity requires displacement and speed requires distance
Explanation:
For calculating speed we require time and distance because speed is defined as the distance per unit time and as speed is a scalar quantity it does not have any direction
But for calculating the velocity we require time as well as displacement because velocity is defined as the displacement per unit time and as velocity is a vector quantity it has direction
Displacement is the shortest distance between the initial position and the final position and it has a specified direction as well
Answer:
2 sig figs.
Explanation:
Sig Fig Rules:
Any non-zero digit is a significant figure.
Any zeros between 2 non-zero digits are significant figures.
Trailing zeros after the decimal are significant figures.
Answer:
C. Electron-negative charge
Explanation:
The electron is subatomic particle that revolve around outside the nucleus and has negligible mass. It has a negative charge.
Symbol= e⁻
Mass= 9.10938356×10³¹Kg
It was discovered by j. j. Thomson in 1897 during the study of cathode ray properties.
He constructed the glass tube and create vacuum in it. He applied electric current between electrodes. He noticed that a ray of particles coming from cathode to wards positively charged anode. This ray was cathode ray.
Properties of cathode ray:
The ray is travel in straight line.
The cathode ray is independent of composition of cathode.
When electric field is applied cathode ray is deflected towards the positively charged plate.
Hence it was consist of negatively charged particles.
While neutron and proton are present inside the nucleus. Proton has positive charge while neutron is electrically neutral. Proton is discovered by Rutherford while neutron is discovered by James Chadwick in 1932.
Symbol of proton= P⁺
Symbol of neutron= n⁰
Mass of proton = 1.672623×10⁻²⁷ Kg
Mass of neutron = 1.674929×10⁻²⁷ Kg
An atom consist of electron, protons and neutrons. Protons and neutrons are present with in nucleus while the electrons are present out side the nucleus.
All these three subatomic particles construct an atom.
