Weight of the carriage 
Normal force 
Frictional force 
Acceleration 
Explanation:
We have to look into the FBD of the carriage.
Horizontal forces and Vertical forces separately.
To calculate Weight we know that both the mass of the baby and the carriage will be added.
- So Weight(W)

To calculate normal force we have to look upon the vertical component of forces, as Normal force is acting vertically.We have weight which is a downward force along with
, force of
acting vertically downward.Both are downward and Normal is upward so Normal force 
- Normal force (N)

- Frictional force (f)

To calculate acceleration we will use Newtons second law.
That is Force is product of mass and acceleration.
We can see in the diagram that
and
component of forces.
So Fnet = Fy(Horizontal) - f(friction) 
- Acceleration (a) =

So we have the weight of the carriage, normal force,frictional force and acceleration.
Answer: True!
Explanation: The force is proportional to the square of the distance between 2 point masses
The watt is a rate, similar to something like speed (miles per hour) and other time-interval related measurements.
Specifically, watt means Joules per Second. We are given that the electrical engine has 400 watts, meaning it can make 400 joules per second. If we need 300 kJ, or 3000 Joules, then we can write an equation to solve the time it would take to reach this amount of joules:
w * t = E
w: Watts
t: Time
E: Energy required
(Watts times time is equal to the energy required)
<u>Input our values:</u>
400 * t = 3000
(We need to write 3000 joules instead of 300 kilojoules, since Watts is in joules per second. It's important to make sure your units are consistent in your equations)
<u>Divide both sides by 400 to isolate t:</u>
<u />
= 
t = 7.5 (s)
<u>It will take 7.5 seconds for the 400 W engine to produce 300 kJ of work.</u>
<u></u>
If you have any questions on how I got to the answer, just ask!
- breezyツ
By definition we have the momentum is:
P = m * v
Where,
m = mass
v = speed
Before the impact:
P1 = (0.048) * (26) = 1.248 kg * m / s
After the impact:
P2 = (0.048) * (- 17) = -0.816 Kg * m / s.
Then we have that deltaP is:
deltaP = P2-P1
deltaP = (- 0.816) - (1,248)
deltaP = -2,064 kg * m / s.
Then, by definition:
deltaP = F * delta t
Clearing F:
F = (deltaP) / (delta t)
Substituting the values
F = (- 2.064) / (1/800) = - 1651.2N
answer:
the magnitude of the average force exerted on the superball by the sidewalk is 1651.2N