Mechanics - Elastic Collisions In 1 Dimension

Question 1

What can you use if you have a problem about the direct impact of 2 particles?

Answer 1

The conservation of linear momentum
And
Newton’s law of restitution

Question 2

What does the speed after the impact depend on in a direct collision?

Answer 2

The material that they are made of

Question 3

What must be true for 2 particles to directly collide?

Answer 3

They must be traveling on the same line

Question 4

What must be true for Newton’s law of restitution to be true?

Answer 4

The collision must happen in free space
Or
In a smooth surface

Question 5

State newton’s law of restitution (long version)?

Answer 5

Question 6

What is the constant e in Newton’s law of restitution?

Answer 6

The constant e is the coefficient of restitution between the particles
0≤e≤1 will always hold true

Question 7

What is true when e=1

Answer 7

When e=1 it is a perfectly elastic collision so the speed of separation is the same as the speed of the speed of approach

Question 8

What is true when e=0

Answer 8

When e=0 it is a perfectly inelastic collision so the particles coalesce on impact

Question 9

What does coalesce mean?

Answer 9

Coalesce means joined together

Question 10

What type material will make e tend to 0?

Answer 10

As the material gets stickier the e will tend to 0

Question 11

What is Newton’s law of restitution ( short version)?

Answer 11

Question 12

What is the long version of Newton’s law of restitution when it is about a direct collision with a smooth plane?

Answer 12

Question 13

With all equations about Newton’s law of restitution (between 2 particles) what is the basic assumption with my short equations?

Answer 13

If the velocity is in the other just put it as a minus sign

Question 14

With all equations about Newton’s law of restitution (between a particle an the wall) what is the basic assumption with my short equations?

Answer 14

Question 15

What needs to be true about a erticle plane for Newton’s law of restitution to be used?

Answer 15

It needs to be a smooth surface

Question 16

What does it mean if the particle collides normally?

Answer 16

Its direction of motion immediately before the collision is perpendicular to the plane

Question 17

What is the formular for the loss of kinetic energy after an impact?

Answer 17

Question 18

What do you know to be true when a string is involved?

Answer 18

If a string becomes taught, both particles experience equal and opposite impulses due to the tension in the string.
Linear momentum is conserved so you can use the principle of the conservation of linear momentum

Question 19

How many kg is there in 1 tonne?

Answer 19

1000

Question 20

What should you do when working with successive impacts?

Answer 20

Draw a new diagram after every impact

Question 21

What do you need to remember with successive impacts?

Answer 21

After a collision has happened the values of u and v will have changed

Question 22

What is the most likely way to work in an inequality sign in these questions?

Answer 22

If 2 particles collide then: