Answer:
When truck is at rest while student is under motion
Explanation:
Since it is obvious that the mass of a truck is more than that of a student, we know that momentum is a product of mass and velocity
P=mv where m represent mass, v is velocity. When the student has more speed than that of truck, he exerts more momentum. The only way a student can exert more momentum is by having more speed while the truck is at rest. In such case, the momentum of truck will be zero while momentum of student will have a value
Answer:
In an elastic collision, the total kinetic energy is conserved, while in an inelastic collision, it is not
Explanation:
Let's define the two types of collision:
- Elastic collision: an elastic collision is a collision in which:
1) the total momentum of the system is conserved
2) the total kinetic energy of the system is conserved
Typically, elastic collisions occur when there are no frictional forces acting on the objects in the system, so that no kinetic energy is lost into thermal energy. An example of elastic collision is the collision between biliard balls.
- Inelastic collision: an inelastic collision is a collision in which:
1 ) the total momentum of the system is conserved
2) the total kinetic energy of the system is NOT conserved
In an elastic collision, part of the total kinetic energy is lost (=converted into thermal energy) due to the presence of frictional forces. An example of inelastic collision is the accident between two cars, in which part of the energy is converted into heat.
Your answer is 3 ( 1 calcium atom and 2 bromine atoms)
Answer: 
Firstly we have to draw the Free Body Diagram (FBD) as shown in the figure attached.
Where the weight 
of the block has an x-component and y-component:
(1)
(2)
As well as the Normal Force 
:
(3)
(4)
In addition, we know 
, then 
In the X-component:
(5)
Substituting (1) in (5):
(6)
In addition, we know 
, where 
is the mass of the block and 
the gravity acceleration, which is equal to 
So:
(7)
(8)
(9) >>>>This is the acceleration of the block
On the other hand, we have the following equation that expresses a <u>relation between</u> the distance 
with the acceleration 
and time 
:
(10)
We already know the value of and calculated , we have to find :
(11)
(12)
(13) >>>This is the time it takes to the block to go from the initial velocity 
to its final velocity 
If the acceleration is the variation of the velocity in time, we can use the following equation to find :
(13)
If 
(14)
(15)
Finally we get the value of the Final Velocity of the block:
