Acceleration means speeding up, slowing down, or changing direction. The graph doesn't show anything about direction, so we just have to examine it for speeding up or slowing down ... any change of speed.
The y-axis of this graph IS speed. So the height of a point on the line is speed. If the line is going up or down, then speed is changing.
Sections a, c, and d are all going up or down. Section b is the only one where speed is not changing. So we can't be sure about b, because we don't know if the track may be curving ... the graph can't tell us that. But a, c, and d are DEFINITELY showing acceleration.
Answer:
B)velocity of object decreases
Explanation:
Consider the positive x axis as positive direction
Assume a body moving in negative x-axis direction
It's acceleration also alone negative x-axis direction
So according to our consideration
velocity and acceleration values are negative
That is both are towards negative x direction
But as both velocity and acceleration are in same direction, MAGNITUDE of velocity increases
But as magnitude increases in negative direction, velocity value decreases
But speed value increases(As speed is scalar and velocity is a vector)
This is true, I believe.
Hope this helps!
Explanation :
An atom is a smallest particle of matter. An atom consists of protons, neutrons and electrons. These are three subatomic particles.
Protons are positively charged species while neutrons are negatively charged species. Electrons revolves around an atom.
Charge :
The charge of an electron is negative or 
The charge of proton is +e or 
Neutron has no charge.
Mass :
Atomic mass of electron is 
Atomic mass of proton is 
Atomic mass of neutron is
Both protons and neutrons are located inside the nucleus at the center.
Charge, atomic mass and location determines the properties of an atom. Atomic mass tells about the number of protons and neutrons inside an atom. Electric charge tells us the number of electrons gain or lost.
