Answer:
The image to the left (with the disks on it)
Explanation:
Interference in any type of wave can be gotten in two forms, constructive interference, and destructive interference.
The constructive interference is between two waves with the same phase, that is, each crest and trough correspond with the crest and trough of the another getting as result a wave with twice the amplitude of the original one.
The destructive interference is between two waves out of phase, in which the crest of one cancels with the trough of another.
If light passes for a slit it will get a diffraction pattern in a screen, at which each bright pattern corresponds to a crest and a dark pattern to a trough, as a consequence of constructive interference and destructive interference in different points of its propagation to the screen.
The circular shape of the disks can be a representation of the wavefront and how the overlaps make constructive and destructive interference in order to get the diffraction pattern.
The work done is calculated by multiplying the Force by the distance. So, 10x20 = 200 joules.
As much as 90% of the matter in the universe my be unseen i.e. dark matter. There is a variety of explanations offered by many astronomers and physicists for this dark matter. It could merely be ordinary material such as ultra-faint stars, cold gas, large or small black holes or dust scattered around the universe, all of which emit or reflect too little radiation for our instruments to detect. It could also consist of exotic, unfamiliar particles that we have not figured out how to observe.
Reflection. It occurs when a wave bounces from the surface of an obstacle
Answer:Take into account the the Earths gravity is 9.8 meters a second
Explanation:
Gravity pulls down on the ball at g=-9.81 m/s^2. Up is positive, down is negative.The ball started at a certain initial velocity of Vi m/s. Time it took is t=4s. Final velocity is Vf=0 m/s, because at the highest point the ball stops moving.
Vf=(g*t)+Vi
Rearrange for Vi.
Vi=Vf-(g*t)
Vi=0-(-9.81*4)=39.24 m/s (upward)
Think about it this way for the non-mathematical approach. The ball stops at the top. The initial velocity gets reduced by 9.81 m/s every second, and reaches 0 m/s at the top. It took 4 seconds, so 9.81*4 is equal to the initial upward velocity.
