Answer:
a. atoms are the basic building blocks of matter. The atom is made of electrons and protons. It contains the chemical identity of an element.
b. Three types of particles that make up an atom are:
electrons - these are negatively charged particles and lightest constituents of an atom.
protons are positively charges and is 1873 times heavier than an electron.
Neutrons are neutral particles having mass equivalent to mass of proton.
Protons and neutrons exist in the center of an atom in nucleus and electrons revolve around the nucleus.
c. An atom is a neutral entity where as an ion is charged. An ion has excess of electrons or lacks electrons due to which it has negative or positive charge. An atom has an equal number of electrons and protons.
d. In a negative ion, the number electrons is greater than number of protons. The atom when gains electrons becomes negative ion.
e. John Dalton proposed Solid sphere model in which tiny invisible particles constitute matter. These invisible particles are atoms and these are indivisible.
Answer:
2.35 m/s²
Explanation:
Given that
Mass of the smaller crate, m₁ = 21 kg
Mass of the larger crate, m₂ = 90 kg
Tensión of the rope, T = 261 N
We know that the sum of all forces for the two objects with a force of friction F and a tension T are:
(i) m₁a₁ = F
(ii) m₂a₂ = T - F, where m and a are the masses and accelerations respectively.
1) no sliding can also mean that:
a₁ = a₂ = a
This makes us merge the two equations written above together as:
m₂a = T - m₁a
If we then solve for a, we would have something like this
a = T / (m₁+m₂)
a = 261 / (21 + 90)
a = 261 / 111
a = 2.35 m/s²
Therefore, the needed acceleration of the small crate is 2.35 m/s²
A. They have negative feelings about the skateboarders. -apex
Repeat the experiment to make sure it gives the same results.
Hope i helped ; )
Definition: Momentum = (mass) x (speed)
OK. Here we go.
Watch closely:
Divide each side
by 'mass' : <span>Momentum / mass = Speed </span>
Did you follow that ?
