Your answer is C.
hope this helps!
Answer:
A. Sulfur _________ group 16 chalcogens
B. Sodium _________ group 1 alkali metals
C. Argon _________ group 18 noble gases
D. Silicon _________ group 14 carbon family
E. Chlorine _________ group 17 halogens
F. Phosphorus_________ group 15 pnicogens
Answer:
V = 0.714m/s
Explanation:
Full solution calculation can be found in the attachment below.
From the principle of conservation of linear momentum, the sum of momentum before collision equals the sum of momentum after collision.
Before collision only the train had momentum. After the collision the train and the boxcars stick together and move as one body. The initial momentum of the train is now shared with the boxcars as they move together as one body. The both move with a common velocity v.
See the attachment below for the solution calculation.
1m = 1000 mm
0,4m = 0,4 * 1000 = 400mm