Unit 4: Conservation of momentum

What does "conservation of momentum" mean?

• The total momentum in the ENTIRE SYSTEM stays the same

• When objects collide, only the 1st object's momentum always stays the same

• When objects collide, their energies stay the samer

• When objects collide, only the 2nd object's momentum stays the same

Tags

NGSS.HS-PS2-2

When is momentum NOT CONSERVED

• if there is an outside force on the system

• If two objects bounce off eachother

• if two objects stick together

• if an object blows up into 2 pieces

Answer explanation

momentum is conserved in EVERY COLLISION.

-not conserved if an outside force (or an impulse) is present

Tags

NGSS.HS-PS2-2

If two objects colliede and BOUNCE OFF EACHOTHER, is Momentum conserved

• yes

• no

Answer explanation

in any collision between objects, moment is conserved (unless there is an outside force)

Tags

NGSS.HS-PS2-2

If two objects collide and STICK TOGETHER is Momentum conserved

• yes

• no

Answer explanation

in any collision between objects, moment is conserved (unless there is an outside force)

Tags

NGSS.HS-PS2-2

If an object EXPLODES INTO PIECES is Momentum conserved?

• yes

• no

Answer explanation

in any collision between objects, moment is conserved (unless there is an outside force)

Tags

NGSS.HS-PS2-2

If there is an outside force, momentum is.....

• Conserved

• Not Conserved

Tags

NGSS.HS-PS2-2

A 10kg object is moving at 5m/s. What is its momentum?

• 50 kgm/s

• 2 kgm/s

• .5 kgm/s

• 0kgm/s

Answer explanation

momentum = mass*velocity

p=m*v

Tags

NGSS.HS-PS2-2

A 10kg object is at rest. What is its momentum equal to?

• 10 kgm/s

• -10 kgm/s

• 0 kgm/s

• 10000 kgm/s

Answer explanation

p=m*v

if at rest v=0

-->p=mass*(0)=0

Tags

NGSS.HS-PS2-2

A 4 kg object has a momentum of -20 kgm/s. What is its veloicty?

• -80 m/s

• -5 m/s

• -.2 m/s

• .2 m/s

Answer explanation

velocity= Momentum/ mass

Tags

NGSS.HS-PS2-2

An object with a momentum of 100kgm/s has a veloicty of 5m/s. What is the object's mass?

• .05kg

• 500 kg

• 20kg

• `05kg

Answer explanation

mass=momentm/velocity

Tags

NGSS.HS-PS2-2