How did you use friction in your design?

If you had more time, what would you change about your design?

Tags

CCSS.RI.11-12.8

CCSS.RI.8.7

CCSS.RI.9-10.7

CCSS.RL.11-12.8

CCSS.RL.9-10.7

The most enjoyable part of the engineering challenge was:

Tags

CCSS.RI.11-12.3

CCSS.RI.6.3

CCSS.RI.7.3

CCSS.RI.8.3

CCSS.RI.9-10.3

What was most frustrating in the design challenge? Why?

Tags

CCSS.RI.2.1

CCSS.RI.3.1

CCSS.RL.1.1

CCSS.RL.2.1

CCSS.RL.3.1

Some challenges faced in working as a team include:

• Communication issues

• Different working styles

• Conflict resolution

• All of the above

If the elf weighs 2 kg. and is traveling at a constant velocity of 0.15 m/s, what would the elf’s momentum be? (Remember momentum = m*v)

• 0.4 kg·m/s
• 1 kg·m/s
• 0.3 kg·m/s
• 0.2 kg·m/s

Tags

CCSS.7.RP.A.3

How would tripling the weight of your sled affect the momentum (assuming the speed remains constant)?

• The momentum would remain the same.

• The momentum would double.

• The momentum would triple.

• The momentum would decrease.

What is the name of the force that acts against the elf’s motion down the slope?

• Friction

• Gravity

• Tension

• Normal force

In the real world, the elf accelerates while sledding down the snow slope because of gravity! Gravity points straight down so only a portion of its acceleration acts in the direction the elf is moving as shown in the diagram. Assuming the elf has a mass of 2 kg., how much force would be needed to stop the elf from sledding down the slope? (Force = mass x acceleration)

• 15 N
• 10 N
• 20 N
• 5 N

The following diagram shows a sled moving along a smooth and frictionless track. Identify the section(s) where the sled will experience unbalanced forces.