Answer:Orient your line of sight directly above the measurement markings.
Explanation: parallax error is a type of systematic error that occurs when an observer views a measurement marking at a wrong angle. This causes a noticeable disparity in results obtained. Therefore the best way to prevent this error is to view and record the data from the correct angle. This can be obtained by:
-Place the measurement device on its edge so it is level with the object being measured.
-Seek out the finest possible edge of the measurement device, or use a device with finer edges.
In conclusion, ask other observers to also take the reading and get an average of their results. It can help cancel out parallax error results.
It's called texture, meaning how something feels.
A antimatter is particle physics, antimatter is a material composed of the antiparticle "partners" to the corresponding particles of ordinary matter. A particle and its antiparticle have the same mass as one another, but opposite electric charge and other quantum numbers.
Answer:
(a) The speed of the target proton after the collision is:
, and (b) the speed of the projectile proton after the collision is: 
.
Explanation:
We need to apply at the system the conservation of the linear momentum on both directions x and y, and we get for the x axle:
, and y axle:
. Now replacing the value given as: 
, 
for the projectile proton and according to the problem 
are perpendicular so 
, and assuming that 
, we get for x axle:
and y axle: 
, then solving for 
, we get:
and replacing at the first equation we get:
, now solving for 
, we can find the speed of the projectile proton after the collision as: and 
, that is the speed of the target proton after the collision.
Not sure the precise concept of "normal observation", but I assume that is observed by "eyes".
Eye observation is basically macroscopic, but when you use a mark, which can be regarded as a point of mass, then it goes to microscopic.
Mark is a reference point which you can compare the relative position change, but with your eyes, first you cannot notice microscopic changes, second the eyes cannot precisely set a stable reference point.
