Momentum and ImpulseMomentum and Impulse

6-16-1

Liner MomentumLiner Momentum

Examine how force and the duration Examine how force and the duration of the collision between objects of the collision between objects affect their momentum.affect their momentum.

Momentum describes an object’s Momentum describes an object’s motionmotion

SI units are the Kgms-1

Vector or scalar?

The bowling ball The bowling ball and the dodge ball.and the dodge ball.– Moving at the same Moving at the same

velocity, which has velocity, which has more momentum?more momentum?

Attempt Practice 6A, p. 209 Answers:

1. 2.5 x 103 Kgms-1 to the right

2. a. 1.2 x 102 Kgms-1 to the NW

b. 94 Kgms-1 to the NW

c. 27 Kgms-1 to the NW

3. 46 ms-1

A change in momentum takes force A change in momentum takes force and timeand time

A change in momentum takes force A change in momentum takes force and timeand time

Stopping the dump truck and the toy Stopping the dump truck and the toy truck moving down the same hill.truck moving down the same hill.

From these examples we see that From these examples we see that momentum (momentum (pp) is closely related to ) is closely related to force (force (FF).).

A change in momentum takes force A change in momentum takes force and timeand time

In simple terms:

1. Small force over long time can produce the same change in momentum as a big force over a _______ time.

Follow-through in sports?

Attempt Practice 6B, p. 211 Answers:

1. 3.8 x 102 N to the right

2. 1.1 x 103 N upward

3. 16.0 kgms-1 to the south

4. a. 9.0 ms-1 to the right

b. 15 ms-1 to the left

Stopping time and distance depends on the Stopping time and distance depends on the impulse-momentum theoremimpulse-momentum theorem

If truck has twice If truck has twice the mass.the mass.And, the brakes are And, the brakes are assumed to apply assumed to apply the same force.the same force.What affect does What affect does this have on this have on stopping time stopping time andand stopping distance?stopping distance?

ptF

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Empty Truck Truck w/ Load (2m)

Attempt Practice 6C, p. 213 Answers:

1. 5.33 s; 53.3 m to the west

2. a. 14 m/s to the north

b. 42 m to the north

c. 8.0 s

3. a. 1.22 x 104 N to the east

b. 53.3 m to the west

A change in momentum over a A change in momentum over a longer time requires less forcelonger time requires less force