Answer:
400 kg.m/s
Explanation:
In a closed system, the principle of conservation of momentum applies. It means. the total momentum before collision equals to the total momentum after collision hence since the initial momentum is given as 400 kg.m/s, the final sum will be the same.
Leaning against a brick wall.
All the others use scientific forces of work.
-Steel jelly.
Answer: The drag force goes up by a factor of 4
Explanation:
The <u>Drag Force</u> equation is:
(1)
Where:
is the Drag Force
is the Drag coefficient, which depends on the material
is the density of the fluid where the bicycle is moving (<u>air in this case)
</u>
is the transversal area of the body or object
the bicycle's velocity
Now, if we assume , and do not change, we can rewrite (1) as:
(2)
Where 
groups all these coefficients.
So, if we have a new velocity 
, which is the double of the former velocity:
(3)
Equation (2) is written as:
(4)
Comparing (2) and (4) we can conclude<u> the Drag force is four times greater when the speed is doubled.</u>
