Motion and Momentum Flashcards
What is Newton’s first law of motion?
An object will remain at rest or continue to travel with constant velocity unless acted upon by a resultant force.
What is Newton’s second law of motion?
The rate of change of momentum of an object is directly proportional to the resultant force acting on the object and acts in the same direction.
What is Newton’s third law of motion?
When two objects interact, they exert equal and opposite forces on each other.
Name the four fundamental forces.
- Gravitational
- Electromagnetic
- Strong nuclear
- Weak nuclear
What is the formula for momentum?
p = mv
What is the principle of the conservation of momentum?
For a system of interacting objects, the total momentum in a specified direction remains constant, as long as no external forces act on the system.
(Total momentum is conserved.)
What are perfectly elastic collisions?
When momentum, total energy and kinetic energy are conserved.
What are inelastic collisions?
When the momentum and total energy are conserved but kinetic energy is not conserved.
What is net force directly proportional to?
Rate of change of momentum
Give the equation for net force.
F = ∆p / ∆t
Derive F = ma from Newton’s second law and state the condition required.
Check Notion.
Mass must be constant.
Define impulse.
The product of force and the time for which this force acts on an object.
(Change in momentum - ∆p)
What are the equations to work out impulse?
- F x t
- m x ∆v
How do you work out impulse from a force-time graph?
Area under the graph
What are the two SI units for impulse and momentum?
kgms^-1
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