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W5 PASS

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W2 PASS

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W5 PASS

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W5 PASS

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TODAY’S SESSION

Lever loverz

KAHOOT

Multi choice quiz :)

SAQs with table groups!

Win of the Weekend!

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TODAY’S SESSION

WIN OF THY WEEKEND

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EFL, FLE, LEF

FLE(e) away from the Q

F

L

E

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FLE(e) away from the Q

F

L

E

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WHITEBOARD:Lever lovers (10 mins)

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WHITEBOARD:Lever lovers (10 mins)

CLASS 1

EFL

CLASS 2

FLE

CLASS 3

LEF

Which diagram goes where :)?

LABEL

  • Arms
  • Load
  • Resistance
  • fulcrum

Mechanical advantage

<1 or >1

Always >1 (because load is closer to the fulcrum than effort)

Always <1 (because effort is closer to the fulcrum than load)

Other examples

Seesaw, scissors

Wheelbarrow, calf raises (gastrocnemius during standing on tiptoe), jaw (biting down)

Bicep curl, biting using jaw, fishing rod, knee during running,

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WHITEBOARD:Lever lovers (10 mins)

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KAHOOT time

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VECTOR

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The rock question✨

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For Class 2 levers, the mechanical advantage is always greater than 1 because the force arm is always longer than the resistance arm!

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Travis the Daredevil, known for launching himself off questionable homemade ramps for internet fame, is preparing for his next stunt. He cycles toward his ramp and pushes off with a horizontal force component of 960 N.He weighs 70 kg, but no worries—his ramp is so perfectly engineered (by YouTube DIY standards) that it magically exerts just enough vertical force to balance his weight.

  1. Assuming the ramp is tilted at a 30º degree angle, what is the total force that Travis applies diagonally along the ramp to one decimal place?

🛞💥Q1 Travis the daredevil

RIP TRAVIS 07.04.2025

Travis’ jump miraculously turned into a purely vertical fall. At the peak of his jump, Travis’s gravitational potential energy (GPE) is 15.4 kJ

b) Calculate the height Travis fell from rounded to two decimal

places

c) Calculate how long Travis will fall for before he experiences

the most painful death imaginable, rounded to two decimal places

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Travis the Daredevil, known for launching himself off questionable homemade ramps for internet fame, is preparing for his next stunt. He cycles toward his ramp and pushes off with a horizontal force component of 960 N.He weighs 70 kg, but no worries—his ramp is so perfectly engineered (by YouTube DIY standards) that it magically exerts just enough vertical force to balance his weight.

  • Assuming the ramp is tilted at a 30º degree angle, what is the total force that Travis applies diagonally along the ramp to one decimal place? =1179.9N

RIP TRAVIS 07.04.2025

Travis’ jump miraculously turned into a purely vertical fall. At the peak of his jump, Travis’s gravitational potential energy (GPE) is 15.4 kJ

b) Calculate the height Travis fell from rounded to two decimal

Places =22.45m

c) Calculate how long Travis will fall for before he experiences

the most painful death imaginable, rounded to two decimal places

=2.14 seconds

🛞💥Q1 Travis the daredevil

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Q2 MAX ARM TORQUE

The data below provides the maximum isometric force and moment arm length for each of the key elbow flexors and extensors at this joint position.

muscle

Max isometric force (N)

Moment arm length (cm)

Triceps long head

900

2.5cm

Triceps lateral head

850

2.8cm

Triceps medial head

800

2.2cm

Biceps brachii

700

3.0cm

Brachialis

750

2.5 cm

calculate the total maximum extension torque (N m) that can be produced at the elbow

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ANEURYSM

calculate the total maximum extension torque (N m) that can be produced at the elbow= 63.9 N m

Q2 MAX ARM TORQUE

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Q3 CRUTCHES!

A patient weighing 90 kg with a broken leg shifts 40% of their body weight onto their crutches.

  1. Calculate the force supported by the crutches to 1 dp. Assume g = 9.8 m/s^2. (1 mark)

  • If each crutch contacts the ground with an area of 15cm2, what is the pressure exerted on the ground by one crutch in kPa to 1 dp? (2 marks)

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Q3 CRUTCHES!

A patient weighing 90 kg with a broken leg shifts 40% of their body weight onto their crutches.

  • Calculate the force supported by the crutches to 1 dp. Assume g = 9.8 m/s^2. (1 mark)

90 kg x 0.4 = 36 kg

36 kg x 9.8 m/s^2 = 352.8 N

  • If each crutch contacts the ground with an area of 15cm2, what is the pressure exerted on the ground by one crutch in kPa to 1 dp? (2 marks)

P = (½) x F/A

= ½ x (352.8 N / 0.0015 m)

= 117,600 N/m^2 = 117.6 kPa

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Q4 nurse lift

A nurse must lift a 70 kg patient from a bed into a wheelchair.

  1. How much force must the nurse use to lift the patient? (1 mark)

  • The nurse lifts the patient to a height of 0.8m in 3 seconds. What is the average velocity of this lift to 3 dp? (1 mark)

  • The nurse has poor lifting technique and sprains her wrist because she distributed most of the force to her forearms. How could she have improved her lifting technique and why would this help? (2 marks)

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Q4 nurse lift

A nurse must lift a 70 kg patient from a bed into a wheelchair.

  • How much force must the nurse use to lift the patient? (1 mark)

Fg of patient = 70 kg * 9.8 m/s^2 = 686 N

The nurse lifts the patient to a height of 0.8m in 3 seconds. What is the average velocity of this lift to 3 dp? (1 mark)

0.8m / 3 s = 0.267m/s

  • The nurse has poor lifting technique and sprains her wrist because she distributed most of the force to her forearms. How could she have improved her lifting technique and why would this help? (2 marks)

Lift with her back and arms. This distributes the force around the body and reduces the amount of force applied to her wrists to reduce the risk of damage.

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Q5 Help Jas and Trav get to the biomed ball!

Travis and Jas are taking a 10m limo that weighs 4000kg to drive to the biomed ball!

The limo’s centre of mass is 4m behind the front of the limo. Where should a 1400kg disco ball be placed so that it’s centre of mass will be right in the middle of the limo?

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Travis and Jas are taking a 10m limo that weighs 4000kg to drive to the biomed ball!

The limo’s centre of mass is 4m behind the front of the limo. Where should a 1400kg disco ball be placed so that it’s centre of mass will be right in the middle of the limo?

=7.86m back

Q5 Help Jas and Trav get to the biomed ball!

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See u next week !

MORE PROJECTILE MOTION SAMPLE QUESTIONS (with worked sols):

https://tuhsphysics.ttsd.k12.or.us/Tutorial/Lessons/Projectile.htm#NewQty

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