Answer:8.69 m/s
Explanation:
Given
mass of Empty train 
velocity of car 
mass of Boulder 
Since no External force is acting therefore conserving Momentum
Train and boulder moves with same velocity after collision



In the graph of the force vs the time:
Force is the gradient of the momentum versus the time.
If we get the area under the curve in this graph:
it will be calculated as : force * time
which gives the change in momentum or the impulse.
Therefore, the area under the curve <span>represents the impulse of the force in a graph of force versus time</span>
The gravitational force acting between them is 
Data given;
- M1 = 45kg
- M2 = 11kg
- r = 2.0m
- G =

To solve this question, we need to apply gravitational force or energy formula.
<h3>Gravitational Force</h3>
This states that the force of attraction between two bodies is equal to the product of their bodies and inversely proportional to the square of their distance apart.
Mathematically;

let's substitute the values and solve

The force of gravity acting between them is 
Learn more on gravitational force here;
brainly.com/question/11359658
Answer:
an example is a bicep curl
Explanation:
A concentric contraction is a type of muscle activation that causes tension on your muscle as it shortens. As your muscle shortens, it generates enough force to move an object.