Mechanics Flashcards
What is a vector?
A measurement with both magnitude and direction.
What is impulse?
Impulse is a change in momentum.
Δp or FΔt or mΔv
Define acceleration.
Acceleration is the rate of change of velocity.
How is speed different from velocity?
Speed is a scalar. It has no direction.
Velocity is a vector. It has direction.
How do you find displacement from a velocity-time graph?
Calculate the area under the graph. If the area is positive or negative, that tells you the direction.
How do you find change in velocity from an acceleration-time graph?
Calculate the area under the graph. If the area is positive or negative, that tells you how the velocity was changing.
Draw a FBD for a car going around a turn on a horizontal road.
(Michal will insert image here.)
Draw a FBD for a mass swinging on a rope when it is at its lowest point.
(Michal will insert image here.)
Draw a FBD for a mass swinging on a rope when it is at its highest point.
(Michal will insert image here.)
An object is accelerating to the left. What do you know about the forces acting on the object?
The net force is to the left. More force left than right
An object is travelling w constant velocity. What do you know about the forces acting on the object?
the net force is 0, they cancel out
An object is travelling w constant speed. What do you know about the forces acting on the object?
It might be going in a circle, and have a net force to the center.
It might have no net force upon it.
If you have a problem with a collision what principle do you use and which equations can you set equal to each other
impulse, conservation of momentum
mΔv=FΔt or mΔv = mΔv
(in some rare questions the mass changes too tho so be careful)
Explain the diff types of collisions
Elastic, inelastic, perfectly inelastic
- In elastic collision all the energy is conserved,
-in inelastic a portion of it is “lost to the room”
-in perfectly inelastic all energy “lost to the room” and the stuff sticks together
MOMENTUM IS ALWAYS CONSERVED
