The forces that were exerted during the air resistance was the gravity.
<u>Explanation:</u>
Air resistance is the frictional power air applies against a moving article. As an article moves, air opposition backs it off. The quicker the article's movement, the more prominent the air obstruction applied against it.
The force acting upon the objects dropped in the air was air resistance and gravity. The force acting upon the objects dropped in the vacuum was gravity only.
For this case we have that the final speed is given by:
Where,
a: acceleration
vo: initial speed
t: time
Clearing the time we have:
Substituting values we have:
it takes 4.375 s for the car to stop
Impulse = Force * times and also Impulse = change in momentum.
Given that the mass does not change, change if momentum = mass * (final velocity - initial velocity)
Given that you know mass and initial velocity (which is the velicity before the cart hits the wall) you need the final velocity (which is the velocity after the cart hits the wall).
Answer: the velocity of the cart after it hits the wall.
1)
The average acceleration of the sprinter can be found by using the following SUVAT equation:
where
v is the final velocity
u is the initial velocity
a is the acceleration
d is the distance covered
In this problem,
u = 0 (the sprinter starts from rest)
v = 11.9 m/s
d = 20.0 m
Solving for a, we find the acceleration:
2) 3.36 s
We can find the time needed to reach this speed by using the SUVAT equation:
where
v is the final velocity
u is the initial velocity
a is the acceleration
t is the time
Here we have
u = 0
v = 11.9 m/s
a = 3.54 m/s^2
Solving for t, we find the time: