Explanation:
Natural selection is the process through which populations of living organisms adapt and change. Individuals in a population are naturally variable, meaning that they are all different in some ways. This variation means that some individuals have traits better suited to the environment than others
Answer:
This depends on what angle they are approaching each other before they collided.The two simple cases are if they are running in the same direction or opposite direction from each other. For either case, use the conservation of momentum equation to solve: M_total*V_result = M1*V1 + M2*V2
Explanation:
Here are two possible solutions.
Head-on collision: M1=78, V1=8.5, M2=72, V2=-7.5 (that's negative because he's running the other way), M_total = 78+72 = 150, so V_result = (78*8.5 - 72*7.5)/150 = 0.82 m/s. Sanity check, they weigh about the same and so most of their velocity should cancel out.
Running the same way: change the sign of V2 to positive so V_result = (78*8.5 + 72*7.5)/150 = 8.02 m/s. Sanity check, they weigh about the same and the resultant speed is between the two starting velocities.
<em>hope it helps:)</em>
Answer:
The answer is the top choice. (-1)
Explanation:
We are dealing with a negative number here, so we should start at negative five on the number line. From here we see that we are subtracting a negative number from it, which means we are really adding. (Review your rules for negative signs if this doesn't make sense.) So we add 4 to -5, and we get -1. Thus, we get the top choice.
Answer
given,
number of dog = 8
mass of each dog= 19 Kg
mass of sled = 210 Kg
average force = 185 Nss
a) writing all the horizontal force
force acting by dog - friction force = (M + 8m) a
8 F_d - μ m g = (M + 8m) a
assuming coefficient of friction of snow be μ = 0.14
8 x 185 - 0.14 x 210 x 9.8 = (210 + 8 x 19 ) x a
a = 3.29 m/s²
b) the kinetic friction of coefficient is less than static friction
hence, we can suggest that acceleration of the sled will increase once the sled start to move.
a > 3.29 m/s²
Answer: 70 N to the East
Explanation:
lets assume east is positive and west is negative, since they are in opposite directions the net external force = F1+F2
Net force = (-60) + 130
Net force = 70
or
Net force = 70 N in the east direction