Answer:
number 4
Explanation:
The reflection of light happens when the light bounces off the reflecting surface. That is described by the last (bottom) schematics.
Therefore, select answer number 4.
W=ΔKE , W=-5000j
KEinitial=(1/2)mv² , KEfinal=0j
ΔKE=-(1/2)mv²
-5000=-(1/2)(100kg)v²
v=10 m/s
Answer:
A) The crossbeam is moving relative to the observer on the platform so the height appears contracted.
Explanation:
The observer on the train and the beam are in the same reference frame. That means observer on the train will measure the proper length of the beam not the contracted length . the observer is outside and the plank is in the moving system,it will appear to be moving.
Answer:
Explanation:
We can calculate the acceleration experimented by the passenger using the formula 
, taking the initial direction of movement as the positive direction and considering it comes to a rest:
Then we use Newton's 2nd Law to calculate the force the passenger of mass m experimented to have this acceleration:
Which for our values is:
