2 (a) Figure 2 shows four items of equipment that can be used in investigations - Edexcel - GCSE Physics - Question 2 - 2022 - Paper 1

To calculate the moment of the force, we use the equation:

$ext{moment of a force} = ext{force} imes ext{distance from pivot}$

Given that the force, F, is 4.0 N and the distance from the pivot is 5.0 cm, we convert the distance to meters: 5.0 cm = 0.05 m.

Thus, the calculation is as follows:

$ext{moment} = 4.0 ext{ N} imes 0.05 ext{ m} = 0.20 ext{ Nm}$

In Figure 4, the ruler is balanced when the clockwise moments equal the anticlockwise moments.

Given:

• Force Y = 3.0 N at a distance of 5.0 cm from the pivot, and
• Force Z = 6.0 N at a distance of 3.0 cm from the pivot.

We can calculate the moments:

• Moment caused by Y: $3.0 ext{ N} imes 0.05 ext{ m} = 0.15 ext{ Nm}$
• Moment caused by Z: $6.0 ext{ N} imes 0.03 ext{ m} = 0.18 ext{ Nm}$

The moments on both sides can be compared, showing that the ruler is balanced when the sum of moments on one side equals the sum on the other side.

Since gears P and R have the same number of teeth and P rotates in the shown direction, gear R will also rotate at the same speed as gear P but in the opposite direction.

Thus, the speed of R is the same as the speed of P, and the direction of rotation of R is opposite to that of P.