Forces And Motion Flashcards
1
Q
State Archimedes principle
A
The upthrust exerted on a body immersed in fluid, partially or fully submerged, is equal to the weight of the fluid displaced.
Upthrust = Αxpg
2
Q
State the principle of moments
A
When a body is in equilibrium, the total clockwise moment about a point is equal to the total anticlockwise moment about the same point.
3
Q
Define a couple
A
Two equal forces that act in opposite directions but not through the same point to produce a turning effect.
4
Q
What is torque of a couple
A
one of the forces x perpendicular distance between the 2 forces
5
Q
How is GPS used to locate a car
A
- With several satellites, the distance from each one is determined.
- Using c and delay time.
- Trilateration is used to locate postion of car (intersection of circles)
6
Q
Why does F=ma not work for particles travelling close to the speed of light
A
The mass of the particles increase as it gets closer to speed of light.
