A-LevelMathematicsMechanics9709/42 · May/June 2017 · Q27 Marks
The diagram shows a wire ABCD consisting of a straight part AB of length 5 m and a part BCD in the shape of a semicircle of radius 6 m and centre O. The diameter BD of the semicircle is horizontal and AB is vertical. A small ring is threaded onto the wire and slides along the wire. The ring starts from rest at A. The part AB of the wire is rough, and the ring accelerates at a constant rate of 2.5 m s⁻² between A and B. [Figure X.X]
- (i)Show that the speed of the ring as it reaches B is 5 m s⁻¹.[1]
- (ii)(a)The part BCD of the wire is smooth. The mass of the ring is 0.2 kg. Find the speed of the ring at C, where angle BOC = 30°.[4]
- (b)Find the greatest speed of the ring.[2]
This question uses a diagram from the original paper, which isn't shown here. Open the full paper from the past papers archive to see it.
Mark scheme
Marking points from the official mark scheme (May/June 2017). The mark or mark type is shown in brackets.
- [B1 AG Using v² = u² + 2as
- M1 Attempting PE loss or KE gain
- A1 Both PE and KE correct both unsimplified
- M1 PE loss = KE gain (3 terms)
- A1 v² = 85 → v = 9.22 ms⁻¹
- M1 PE loss = KE gain
- A1 v² = 145 → v = 12(.0) ms⁻¹
Write your answer and get it marked
On Oracle Prep you can write or photograph your own answer and have it marked by AI against this mark scheme, with feedback on what you missed.
Sign up free →