Hello!
This is a matter of superposition.
When the waves peak at the same time and place, they produce constructive interference, meaning the waves interact together in a positive way, to make a wave with Amplitude of both waves added together. When the peaks differ however, at the same time and place, then it is destructive interference and the waves essentially cancel each other out.
Hope this helps. Any questions please just ask. Thank you kindly.
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:
a) The electric field at that point is 
newtons per coulomb.
b) The electric force is 
newtons.
Explanation:
a) Let suppose that electric field is uniform, then the following electric field can be applied:
(1)
Where:
- Electric field, measured in newtons per coulomb.
- Electric force, measured in newtons.
- Electric charge, measured in coulombs.
If we know that 
and 
, then the electric field at that point is:
The electric field at that point is newtons per coulomb.
b) If we know that and 
, then the electric force is:
The electric force is newtons.
Answer:
At the center of the object
At the end of the object farthest away from the ground
At the center of gravity of the object
At end of the object closest to the ground
Explanation:
