Momentum and Torque Flashcards
1
Q
Momentum
A
-
Momentum is defined as the product of mass and velocity
- p = mv
- Any object with a velocity must have:
- Momentum
- Kinetic energy
2
Q
Conservation of Linear Momentum
A
- The conservation of linear momentum states that the momentum of a system is conserved
- m1v1initial + m2v2initial = m1v1final + m2v2final
- Generic system involving the
3
Q
Impulse
A
- Impulse results from an impact force acting on an objet during a collision that changes the object’s momentum
4
Q
Impulse in Two Object Collision
A
- In a two object collision (where momentum is conserved), both objects experience the same exact magnitude of impulse
- As a result, lighter objects generally experince a greater change in velocity than heavier objects
5
Q
Small Object Hitting Wall Collision
A
- Collision of a small moving object with a large stationary barrier
- Perpendicular or angled to barrier
- Impulse (change in momentum) is greater for the former; velocity remains in same direction throughout
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6
Q
Small Object Hitting A Stationary Small Object Collision
A
- Collision of a moving object and a stationary object of comparable mass
- Inelastic
- m1v1initial = (m1 + m2)vfinal
- Elastic (m1 =m2)
- m1v1initial = m2v2final
- Rebound
- m1v1 = m1vfinal + m2vfinal
- Inelastic
7
Q
Two Small Moving Objects Colliding
A
- Collision of two moving objects
- At an angle
- Inelastic (KE not conserved)
- Elastic (KE conserved)
- Head on
- Inelastic (KE not conserved)
- Elastic (KE conserved)
- At an angle
8
Q
Why Is KE Not Conserved in Inelastic Collisiosns?
A
- Some energy is used in the deformation of the object; this is how the two objects end up sticking together; speed is most definitely reduced
9
Q
Torque
A
- Torque (τ) is simply a measurement of the ability of a force to cause rotation about a pivot point
- τ = rFperpendicular
- Perpendicular to r
- τ = rFsin(θ)
- Force applied parallel to r will result in zero torque
10
Q
Rotational Equilibirum
A
- A spinning rigid body that rotates at constant angular velocity is said to be in rotational equilibirum