Answer:
I think the answer is b but i cannot confirm cuz this is a challenging question
Answer:

ΔK = 2.45 J
Explanation:
a) Using the law of the conservation of the linear momentum:

Where:


Now:

Where
is the mass of the car,
is the initial velocity of the car,
is the mass of train,
is the final velocity of the car and
is the final velocity of the train.
Replacing data:

Solving for
:

Changed to cm/s, we get:

b) The kinetic energy K is calculated as:
K = 
where M is the mass and V is the velocity.
So, the initial K is:



And the final K is:




Finally, the change in the total kinetic energy is:
ΔK = Kf - Ki = 22.06 - 19.61 = 2.45 J
Answer:
3.1 m/s
Explanation:
The total distance she has to run is the addition of the three lengths:
47 + 63 + 76 = 186 meters.
She needs to cover it one minute (60 seconds). Therefore her speed must be:
186 m / 60 s = 3.1 m/s
Answer:
According to Newton's Second Law of Motion :
Where,
F = Force Applied
m = Mass of the object
a = Acceleration
Now, we will use this law to solve this question.
Given :
Acceleration or a = 15.3 m/s²
Force = 44 N
Mass = ?
Substitute, the given values in the formula.
F = ma
⇒ m = F/a
m = 44/15.3
<u>m = 2.9 kg</u>