For atoms in the periodic table, the given mass number is the sum of the number of the protons (also called the atomic number) and the number of the neutrons inside its nucleus. Mathematically,
mass number = atomic number + number of neutrons
Substituting,
39 = 19 + n
n = 39 - 19 = 20
Therefore, the answer is not found in the choices.
Answer:
Option A is the correct answer.
Explanation:
The instantaneous acceleration = Change in velocity in velocity/Time taken
The slope of the graph should give instantaneous acceleration.
Slope of a graph = Change in value of Y -axis / Change in values of X -axis
Comparing both the equations
Change in value of Y -axis = Change in velocity in velocity
Change in values of X -axis = Time taken
So velocity values should be on the Y axis and Time values should be on the X axis.
Option A is the correct answer.
Answer
given,
mass of steel ball, M = 4.3 kg
length of the chord, L = 6.5 m
mass of the block, m = 4.3 Kg
coefficient of friction, μ = 0.9
acceleration due to gravity, g = 9.81 m/s²
here the potential energy of the bob is converted into kinetic energy



v = 11.29 m/s
As the collision is elastic the velocity of the block is same as that of bob.
now,
work done by the friction force = kinetic energy of the block




d = 7.23 m
the distance traveled by the block will be equal to 7.23 m.
Answer:
2.61 J
Explanation:
Since potential energy U = mgy where m = mass of object, g = acceleration due to gravity = 9.8 m/s² and y = height of object above the ground.
Now for the coffee mug, m= 0.422 kg and it is 0.63 m on a table, so it is 0.63 m above the ground. Thus, y = 0.63 m.
We compute U
U = mgy
= 0.422 kg × 9.8 m/s² × 0.63 m
= 2.605 J
≅ 2.61 J
So, the potential energy of the mug with respect to the floor is 2.61 J
False. What actually determines the properties of elements are the electrons, or aka valence electrons. They are used to bond, which determines its properties.