An experimental group is the group in the experiment that receives the variable that is being tested. Only one variable is tested at a time. The control group does not receive the test variable. the experimental groups are used to find the answers in a experiment
Answer:
a) 3.632 m/s
b) 0.462 m/s
Explanation:
Using the law of conservation of momentum:
..........(1)
Substituting the above values into equation (1) and make V2 the subject of the formula:
..................(2)
Using the law of conservation of kinetic energy:
.......(3)
Substitute equation (2) into equation (3)
Substituting 
into equation(2)
If the intelligent aliens on that distant planet could receive our signal, and then reply to us INSTANTLY with no delay, then our Scientists on Earth would hear the response <em>eight years after</em> they sent their original greeting.
Light and radio waves both travel through space at the same speed. If our scientists sent a radio transmission to that distant planet, it would take four years for the radio message to get there and be heard. Any response would take four years to travel back to us. If the aliens didn't dilly-dally and sent their response immediately, the round trip would total up to eight years.
Answer:
v_average = 15 m / s
Explanation:
The average speed can be found in two ways,
* taking the distance traveled and divide it by the time spent
* taking the velocities in each time interval and then finding the weighted average by the time fraction
v_average = 1 / t_total ∑ 
vi ti
Let's apply this last equation
Total time is
t = t₁ + t₂
t = 10 + 10 = 20 min
v_average = 10/20 10 + 10/20 20
v_average = 10/2 + 20/2
v_average = 15 m / s
The correct option is D.
During hurricane, the most important thing is to get people out to safety in order to save their lives. Training the community about safety evacuation route is by far the better idea because it provide immediate safety from the natural hazard. The second idea is not a good one at all, because if food are stocked in every house in the community, the food will be destroyed alongside other things during the hurricane.
