Answer:
Final velocity, v = 0.28 m/s
Explanation:
Given that,
Mass of the model, 
Speed of the model, 
Mass of another model, 
Initial speed of another model, 
To find,
Final velocity
Solution,
Let V is the final velocity. As both being soft clay, they naturally stick together. It is a case of inelastic collision. Using the conservation of linear momentum to find it as :



V = 0.28 m/s
So, their final velocity is 0.28 m/s. Hence, this is the required solution.
Answer:
Skew Lines
Explanation:
Two distinct lines intersect at most one point; two distinct planes intersect in at most one line. If two coplanar lines do not intersect, they are parallel/ Two lines which are not coplanar cannot intersect and are called skew lines.
Answer: Yes it possible for a system to have negative potential energy, since the choice of the zero of potential energy is arbitrary.
Explanation:
Potential energy is defined as the energy present in an object due to its position.
Mathematically, P.E = mgh
A potential energy can be negative also. This is because zero potential energy is arbitrary. For example, at the top of a building the choice of potential energy can be zero.
Therefore, the potential energy below the building will be negative.