LEARNING TARGET:

WORDS O' THE DAY:

• momentum (p=mv)
• impulse (∆p or F∆T)

CALENDAR:

FORMULAE OBJECTUS:

Note: Remember, "p" is our symbol for momentum and "J" is the symbol for impulse

p=mv

J = ∆p

J = p_f - p_i

J = mv_f - mv_i

J = F∆t

m₁v_1i + m₂v_2i = m₁v_1f + m₂v_2f

WORK O' THE DAY:

Let's check the viewing calendar!

Now let's review the lab report that you have due... when?

 

• The very fastest Major League Baseball pitchers can throw up around 101 mph (45.1 m/s) -- The record for the fastest pitch ever clocked on radar was 105.8 mph. The mass of an official MLB baseball is about .145 kg (there is a range of masses actually: from .14175 kg to .14883 kg -- but I digress)

• What is the the momentum (p) of such a fastball just AFTER it leaves the pitcher's hand? FULL WOLGEMUTHIAN!

• Check out the picture below. How does that relate to our conversations of momentum and ESPCIALLY of impulse?

1) Now let's say that you can impart 750 N of force onto the SAME ball traveling the SAME velocity using the bat. How long must the bat be in contact with the ball to completely stop the ball's forward momentum (as per usual, we will ignore air friction, wind, rain, sleet, hail and the usual 'nos')?

• Take that exact same situation, and let's say you didn't *quite* take a good whack at the ball and you were only able to impart 501. N of force on the ball. How long must the ball be in contact with the bat to halt the momentum of that ball?

• If the bat is in contact with that ball for 0.0087 seconds (!), how much force did that bat make with the ball? FULL WOLGEMUTHIAN!

Consider the following scenario:

Would you rather be hit in the head with a 2.5 kg bag of bricks or a 2.5 kg bag of feathers? (Each is swung at the same velocity)

 

Let's say that an object of unknown mass is traveling at a velocity of 14.3 m/s to the right where it smacks into a much lighter object (mass = 1.115 kg) moving to the left at a somewhat meager 2.123 m/s. What further information do you need in order to analyze that problem?

 

Once you know that, further discuss with your team on what happens to the two objects after the collision?

 

 

Now let's say the final velocity of the 1st object is 12.90 m/s and the final velocity of the 2nd object is 29.32 m/s.

 

Why has the velocity of the 2nd object increased so much?

Why has the velocity of the 1st object decreased so little?

 

 

Please calculate the mass of the first object.

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Practice Problems 1- 10: Pick at least 4 of those and then work on setting up the infamous BLUE FONT problem #10