Vocab
This is the product of mass and velocity.
What is momentum? (p = mv)
Momentum, velocity, and force all belong to this category of quantities.
What are vector quantities?
The impulse-momentum theorem states that impulse equals this.
What is change in momentum (J = Δp)?
If mass doubles and velocity stays the same, momentum does this.
What is double (increases by a factor of 2)?
Airbags protect passengers by doing this to the collision time.
What is increasing (extending) the collision time?
Calculate the momentum of a 8 kg object moving at 5 m/s.
What is 40 kg·m/s?
This is defined as force multiplied by time.
What is impulse? (J = Ft)
Mass, speed, and time belong to this category.
What are scalar quantities?
To increase impulse without changing force, increase this variable.
What is time?
If velocity triples and mass stays the same, momentum does this.
What is triple (increases by a factor of 3)?
A baseball player's follow-through increases this physical quantity on the ball.
What is impulse (and therefore change in momentum)?
A force of 35 N acts on an object for 6 seconds. Calculate the impulse.
What is 210 N·s?
This property describes an object's resistance to changes in its motion.
What is inertia?
A ball moves east at 5 m/s. Its momentum is 10 kg·m/s east. This tells you momentum is this type of quantity.
What is a vector?
A 4 kg object accelerates from 0 to 10 m/s. This is the impulse experienced.
What is 40 N·s?
Object A: 2 kg at 9 m/s. Object B: 6 kg at 3 m/s. This describes their momenta.
What is equal? (both have p = 18 kg·m/s)
A gymnast bends her knees on landing to reduce this.
What is the force on her joints?
An object has momentum 72 kg·m/s and a mass of 9 kg. Solve for its velocity.
What is 8 m/s?
These are two correct SI units for impulse.
What are kg·m/s and N·s?
When a ball bounces off a wall and reverses direction at the same speed, this quantity is NOT zero.
What is the change in momentum (Δp)?
A force of 60 N acts for 5 seconds. This is the impulse delivered.
What is 300 N·s?
An object's mass is halved and velocity is doubled. Momentum does this.
What is stay the same?
A 50 kg person stops from 10 m/s in 0.5 s. This is the average stopping force.
What is 1,000 N?
A 5 kg object experiences an impulse of 60 N·s. Using the impulse-momentum theorem, solve for the time if the average force was 12 N.
What is 5 seconds?
This term describes the difference between final and initial momentum.
What is change in momentum (Δp)?
What is impulse?
This is why two objects with the same speed but opposite directions do NOT have the same momentum.
Reveal answer
What is direction? (momentum is a vector)
A 3 kg ball receives an impulse of 24 N·s and had an initial velocity of 2 m/s. This is its final velocity.
What is 10 m/s?
An object's mass is tripled and velocity is halved. Momentum changes by this factor.
What is 1.5 (increases by 50%)?
Crumple zones in cars increase collision time from 0.1 s to 0.5 s. For the same crash, force is reduced by this factor.
What is 5 (force is 5 times smaller)?
A 4 kg ball moving at 3 m/s is struck by a force of 40 N for 0.5 s. Using the impulse-momentum theorem, solve for the ball's final velocity.
What is 8 m/s?