| Exam Board | Pre-U |
|---|---|
| Module | Pre-U 9794/3 (Pre-U Mathematics Paper 3) |
| Year | 2012 |
| Session | June |
| Marks | 4 |
| Topic | Constant acceleration (SUVAT) |
| Type | Particle on inclined plane |
| Difficulty | Moderate -0.8 This is a straightforward SUVAT problem combined with Newton's second law. Students need to find acceleration from kinematics (s=10, u=0, t=4), then apply F=ma with T-mg=ma to find tension. It's a standard two-step exercise requiring only routine application of familiar formulas with no conceptual challenges or problem-solving insight. |
| Spec | 3.02d Constant acceleration: SUVAT formulae3.03c Newton's second law: F=ma one dimension |
The equation of motion is $T - 20g = 20a$ — B1
Using 'suvat', assuming zero initial speed:
$10 = 0 + 0.5a \times 4^2$ — M1
$a = 1.25$ ms$^{-2}$ — A1
$T = 225$ — A1 [4]
**Total: [4]**8 A crane lifts a crate of mass 20 kg using a light inextensible cable. The crate starts from rest and ascends 10 metres in 4 seconds during which time a constant tension of $T \mathrm {~N}$ is applied in the cable. Find the value of $T$.
\hfill \mbox{\textit{Pre-U Pre-U 9794/3 2012 Q8 [4]}}