6. Further Mechanics Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What is an impulse?

A
  • The change in momentum.

- given by Ft=p

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Derive impulse from newtons second law?

A

F=ma
a=Δv/Δt

∴ F=Δ(mv)/Δt
∴ FΔt = Δmv = Δp

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How would you go about conserving momentum in two dimensions?

A

Resolve the motion into components (along the perpendicular axis).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the difference between an elastic and inelastic collision?

A

Elastic: kinetic energy is conserved.

Inelastic: kinetic energy is not conserved (converted into/transferred from other forms).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Is an explosion elastic or inelastic?

A

Inelastic.

As the kinetic energy after is greater than before.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Derive Eₖ = p²/2m using formulas for kinetic energy and momentum.

A
Eₖ = ½mv²
p = mv

v= p/m
∴ Eₖ = ½m(p²/m²)
= ½(p²/m)
= p²/2m

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is a radian?

A
  • The angle in the sector of a circle when the arc length of that sector is equal to the radius of the circle.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is angular displacement?

A
  • The angle turned through in a given direction…

- in radians or degrees.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is angular velocity?

A
  • The angle an object moves through per unit time.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How do you calculate the angular velocity from the angular displacement?

A

Δθ/Δt

How well did you know this?
1
Not at all
2
3
4
5
Perfectly