Newton's laws of motion and momentum- red pages

State Newton’s first law of motion

the velocity of an object will only change if a resultant force is acting upon it

Identify the ways in which the velocity of an object can change

starting to move, stopping moving, speeding up, slowing down and changing direction

State Newton’s second law of motion

the net/resultant force acting on an object is equal to the rate of change of momentum of the object

State the formula for net/resultant force

F=Δρ(mv)/t

State the formula for bet/resultant force in the special case where mass is constant

F=ma

State Newton’s third law

if object A exerts force on object B, object B will exert a force back on object A this is the same size, same type and acts in the opposite direction along the same line

State four features of the forces in a Newton’s third law pair

same size, same type, acting in opposite directions, acting on different objects

State the principle of conservation of momentum

the total momentum of a system of objects remains constant, as long as there is no net external force acting on the system, momentum before equals the momentum after

What is elastic collision?

a collision in which the total kinetic energy of the objects involved is the same after the collision as before the collision

What happens to the objects in a perfectly inelastic collision?

they stick together

State and explain whether kinetic energy is conserved in an explosion

kinetic energy is not conserved, because the total kinetic energy of the pieces after the collision is greater than the kinetic energy of the object before it explodes.

State two quantities that are conserved in a chemical explosion

total momentum, total energy

Define the impulse of a force

the impulse of a force is the size of the force multiplied by the time it acts for; Impulse=FΔt

State the relationship between impulse and momentum

impulse= change in momentum

State the equation given by the conservation of momentum for two objects that collide but do not stick together

m1u1+ m2u2= m1v1+ m2v2

State the equation given by the conservation of momentum for two objects that collide and stick together

m1u1+ m2u2= mv

State the equation given by the conservation of momentum for two objects that explodes into two pieces

mu= m1v1+ m2v2