Answer:
1.5 m/s
Explanation:
Momentum is conserved and conservation of momentum is
p₁ + p₂ = p'₁ + p'₂
or
m₁v₁ + m₂v₂ = m₁v'₁ + m₂v'₂
In our problem, after collision v'₁ will be equal to v'₂.
Since objects are identical m₁ = m₂
m(v₁+ v₂) = 2m x v'₁
(2m/s + 1m/s) = 2v'₁
v'₁ = v'₂ = 1.5 m/s
From the average speed you can fix an equation:
Average speed = distance / time
You know the average speed = 65.1 kg / h, then
65.1 = distance / total time,
where total time is the time traveling plus 22.0 minutes
Call t the time treavelling and pass 22 minutes to hours:
65.1 = distance / [t + 22/60] ==> distance = [t + 22/60]*65.1
From the constant speed, you can fix a second equation
Constant speed = distance / time traveling
94.5 = distance / t ==> distance = 94.5 * t
The distance is the same in both equations, then you have:
[t +22/60] * 65.1 = 94.5 t
Now you can solve for t.
65.1t + 22*65.1/60 = 94.5t
94.5t - 65.1t = 22*65.1/60
29.4t = 23.87
t = 23.87 / 29.4
t = 0.812 hours
distance = 94.5 km/h * 0.812 h = 76.7 km
Answers: 1) 0.81 hours, 2) 76.7 km
It would be A because it would make sense
Hello there!
I hope you and your family are staying safe and healthy during this unprecendented time.
A) What is the work done?
Answer: We need to use the formula



B) What is the work done on the cart by the gravitational force?
Alright, we know that the gravitional force is perpendicular to the diplacement. Therefore, we gonna use the following formula:


C) What is the work done on the cart by the shopper?
This is the easier part, since we already know that the work done by the shopper is the same as the work done by the friction force

D) Find the force the shopper exerts, using energy considerations.

E) What is the total work done?
You just need to add them:

The answer is calcium. I just did it and it was correct