This question was reportedly very unpopular as it was attempted by only very few candidates. In part (a), candidates were expected to sketch the diagram for easier understanding of what needed to be done.
From the diagram, R = mg cosq = 8 cos 40o = 6.13N
The required force F = mg sinq = 0.8 x 10 x sin 40o = 5.14N
In part (b), mass = 0.8kg, u = 5i + 3j; and v = 5i + 12j. Impulse ft = m(v – u) = 0.8[(5i + 12j) – (5i + 3j)] = 0.8[0 + 9j] = 7.2j Kg ms-2.
To find the acceleration, ft = mat = 7.2 kgms-2 ⇒ a =  =  = 4.5ms-2. |
