investigation of the laws of equilibrium for co-planar forces

Question 1

how did the student measure the upward forces and downward forces?

Answer 1

upward forces are measured using the newton balances. downward forces are measured using the 1N masses placed along the metre stick and the weight( a downward force) is measured using a newton balance placed at the 50cm mark

Question 2

explain how to calculate the clockwise and anti-clocktwise moments acting on the meter stick

Answer 2

select a fulcrum(0cm mark) and identify forces that would turn the metre stick clockwise and anticlockwise. calculate the moments (force x perpendicular distance from the force to fulcrum)

Question 3

explain how these values could be used to verify the two laws of equilibrium

Answer 3

if the vector sum of forces in any direction is 0. if the anticlockwise and clockwise moments about any point is 0

Question 4

how did the student know the metre stick was in equilibrium

Answer 4

it was not moving in any direction- completely at rest

Question 5

how did the student find the weight of the metre stick?

Answer 5

by using a newton balance placed at the centre of gravity

Question 6

why is the centre of gravity of the metre stick usually not at the 50cm mark

Answer 6

manufacturing inconsistencies, or damage to the stick means the centre of mass is not at the exact centre.

Question 7

describe how the centre of gravity of the metre stick was found

Answer 7

by balancing the metre stick from a position in the centre so that it remains at rest

Question 8

why was it important to have the spring balances hanging vertically

Answer 8

for the laws of equilibrium to hold, the forces being calculated must lie in the same place(co-planar). By hanging the spring balances vertically, it ensures that the metre stick rests horizontally