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:
437 J
Explanation:
Parameters given:
Weight of child, W = 230 N
Height of swing, h = 1.9 m
Gravitational Potential Energy is given as:
P. E. = m*g*h = W*h
m = mass
h = height above the ground
W = weight
P. E. = 230 * 1.9
P. E. = 437 J
The same 500N, is the Newton’s Third Law.
First, we must find the vertical distance traveled upwards by the ball due to the throw. For this, we will use the formula:
2as = v² - u²
Because the final velocity v is 0 in such cases
s = -u²/2a; because both u and a are downwards, the negative sign cancels
s = 14.5² / 2*9.81
s = 10.72 meters
Next, to find the time taken to reach the ground, we need the height above the ground. This is:
45 + 10.72 = 55.72 m
We will use the formula
s = ut + 0.5at²
to find the time taken with the initial velocity u = 0.
55.72 = 0.5 * 9.81 * t²
t = 3.37 seconds
C.figure 3 is the answer had the same and got is right
