Humans’ Intelligent Inventions with Simple Physics Tricks

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50g on 70cm

50g on 60cm

50g on 30, 2 x 50g on 65cm

Hypothesis and questions

How does the force required to lift the mass vary for the different types of configurations?

Pulleys with the greatest difference value of the displacement will have the greatest mechanical advantage.

How do the mass effect the turning force as it’s further away from the pivot?

The turning force will become stronger as it gets further away from the pivot.

How does the size of the wheel change the force required to lift the mass?

The greater the size of the wheel, the less force required to lift the mass

What do you estimate the mass of the ruler to be?

The estimated value of the mass of the ruler is the R value of the formula (E) times 100.

Results and Data

Pulleys data

Pulley config.

Mass attached (kg)

Weight of mass (N)

Force required (N)

Mechanical Advantage

1

0.5

5

5.4

0.926

2

0.5

5

1.4

3.571

3

0.5

5

2.8

1.786

Use formula (A) to calculate mechanical advantage

MA=Weight of LoadApplied Force=5/5.4=0.926

MA=Weight of LoadApplied Force=5/1.4=3.571

MA=Weight of LoadApplied Force=5/2.8=1.786

Pulley configuration 2 showed the greatest mechanical advantage which proves the hypothesis. According to formula (B), the work done is equal to the force times the distance. Pulley configuration had the greatest displacement to do the same amount of work as 1 and 2 which led to the least amount of force required. The values of the mechanical advantage is slightly off but valid because the mechanical advantage for configuration 1 should equal to 1 because The distance the mass was lifted is equal to the distance of the force applied. Also for configuration 2, the distance the mass traveled is a quarter of the distance the force was applied which should make the mechanical advantage result in 4. Lastly, configuration 3 should have been 2 because the distance the mass traveled is half of the distance of the force applied.

Balance Beam

Configuration 1

Mass

Hole number

Left / right side

50g

2

L

20g

5

R

Configuration 2

Mass

Hole number

Left / right side

100g

1

L

20g

2

R

20g

3

R

Configuration 3

Mass

Hole number

Left / right side

100g

3

L

50g

4

R

20g

2

R

20g

3

R

The hypothesis was proven. In all configurations, the turning force was stronger as the mass moves away from the pivot. The hole number times the mass of the left side is all equal to the mass times the hole number of the right side. No error is shown in this experiment.

Wheel and Axle

Data for the wheel and axle lab

Weight attached (N)

Wheel size weight attached to

Force needed to lift (N)

Wheel size force meter attached to

Mechanical Advantage

1

Large

3.5

Small

0.286

1

Large

0.4

Medium

2.5

2

Medium

0.5

Large

4

2

Medium

4

Small

0.1

2.6

Small

0.1

Medium

2.6

2.6

Small

0.7

Large