A block of mass 8 kg is placed on a rough plane which is inclined at an angle of 18° to the horizontal. The block is pulled up the plane by a light string that makes an angle of 26° above a line of greatest slope. The tension in the string is TN (see diagram). The coefficient of friction between the block and plane is 0.65.

Mark scheme

Marking points from the official mark scheme (Oct/Nov 2022). The mark or mark type is shown in brackets.

1. [*M1] Attempt at N2L parallel to the plane 4 terms. Allow sign errors, sin/cos mix, allow g missing.
2. [A1] T cos 26 - 8g sin18 - F = 8×0.2 Allow with their F.
3. [*M1] Attempt at resolving perpendicular to the plane 3 terms Allow sign errors, sin/cos mix, allow g missing.
4. [A1] R+T sin 26 = 8g cos 18
5. [DM1] Use of F =0.65R to get an equation in T only R is a linear combination of a component of T and a component of weight. Using equations with no missing terms.
6. [M1] Solve for T Dependent on all 3 previous M marks.
7. [A1] T = 64(.0) N
8. [M1] Complete method to find s using constant acceleration formula(e) Finding distance moved between t=3 and t = 4, must be using a = 0.2
9. [A1] Distance = 0.7 m If 0 marks scored then SCB1 for s = 1/2 × 0.2 × 4² = 1.6