**(i)**

| B1 | Any one force in correct direction correctly labelled with arrow or all forces with correct directions and arrows.

| B1 | All correct (Accept words for labels and weight as $W, mg, 147 \text{ (N)}$) No extra or duplicate forces. Do not allow force and its components unless components are clearly distinguished, eg by broken lines.

| | 2 |

**(ii) Either** Up the plane

$Pcos20 - 15 \times 9.8 \times sin20 = 0$ | M1 | Attempt to resolve at least one force up plane. Accept mass not weight. No extra forces. If other directions used, all forces must be present but see below for resolving vertically and horizontally.

$P = 53.50362\ldots$ so $53.5$ (3 s.f.) | A1 | Accept only error as consistent s $\leftrightarrow$ c.

| A1 | cao

| | 3 |

**Or Vertically and horizontally**

$R cos 20° = 15g$, $R sin 20° = P$ | M1 | Attempt to resolve all forces both horizontally and vertically and attempt to combine into a single equation. No extra forces. Accept $s \leftrightarrow c$. Accept mass not weight.

$P = \frac{15g}{cos 20°} \times sin 20°$ | A1 | Accept only error as consistent s $\leftrightarrow$ c.

$P = 53.5$ (3 s.f.) | A1 | cao

| | 3 |

**Or Triangle of forces**

Triangle drawn and labelled | M1 | All sides must be labelled and in correct orientation; three forces only; condone no arrows

$\frac{P}{15g} = tan 20°$ | A1 | Oe

$P = 53.5$ (3 s.f.) | A1 | cao

| | 3 |

| | 5 |

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