Finds the value of θ: θ = ( ). Accept awrt θ = 77.5 ( ). A1 ft 1.1b

Transcription

1 1a States that a = a = 0 may be seen. B1 1.1b 4th States that b = b = 0 may be seen. B1 1.1b () Understand Newton s first law and the concept of equilibrium. 1b States that R = i 9j (N). M1 1.1b 4th States that the magnitude of R 9 M1 1.1b States R 85 (N) or R = 9.1 (N). Accept awrt 9. (N). A1 1.1b Calculate resultant forces using vectors. 1c 9 States tan θ Finds the value of θ: θ = ( ). Accept awrt θ = 77.5 ( ). M1 1.1b 4th Calculate resultant forces using vectors. () (7 marks) 1b Award second method mark and accuracy mark for a correct answer using their R. 1c Award ft marks for correct answer using their R vector from part a. Education Ltd 017. Copying permitted for purchasing institution only. This material is not copyright free.

2 a States F = ma or implies use of F = ma For example, 10 = 80 a is seen. Correctly finds 3 a (m s ) or a = 1.5 (m s ). States v = u + at, or implies its use. For example, t is seen. 4th A1 1.1b M1 3.1b one direction. Finds t = 1 (s). (4) b States that v u as or implies it use by writing s Correctly finds s = 108 (m). M1.a 4th one direction. c States that the cyclist is not a particle, or states that the resistive force is unlikely to be constant. () B th (1) one direction. (7 marks) a Award ft marks for a correct answer using their value for acceleration. b Award ft marks for a correct answer using their value for acceleration. Education Ltd 017. Copying permitted for purchasing institution only. This material is not copyright free.

3 3a 10 a Either states that tan30 or tan 60 a 10 Correctly find a 10 3 M1 1.1b Interprets a in the context of the question, stating a 10 3 A1 3. M1 1.1b 5th 3b States that the magnitude of R States R = 0 (N). M1 1.1b 5th 3c States F = ma or implies use of F = ma. For example 0 = 6 a is seen. 10 Correctly finds a m s. 3 () 5th () 3d 1 States that s ut at or implies it use by writing (0) t t 3 Solves to find t 8 6 (s). Accept awrt 19.6 (s). () (9 marks) 3b Award ft marks for a correct answer using their value from part a for the i component of the force. 3c Award ft marks for a correct answer using their value from part b for the resultant force. 3d Award ft marks for a correct answer using their value from part c for the acceleration. Education Ltd 017. Copying permitted for purchasing institution only. This material is not copyright free.

4 4a States, or implies in a subsequent step, that the resistances to motion will total 1600k (N). (Any variable is acceptable.) Uses F = ma to write k 1600(0.4) Solves the equation to find k = 1.6 A1 1.1b Finds the resistance forces acting on the trailer: Rtrailer (N). M1 3.1b 4th A1 1.1b (4) 4b Demonstrates an understanding that the resultant force for the trailer is T 640, or for the car is T Either states T (0.4) using the trailer or states T 100(0.4) using the car. M1 3.1b 4th Correctly finds T = 800 (N). 4c Uses F = ma to write 640 = 400a 4th Correctly solves to find a = 1.6 m s Uses v u as to write Correctly solves to find s = (m). Accept awrt 195 (m). 0 5 ( 1.6)s M1 3.1b (4) 4d States the acceleration of the car will be equal to the acceleration of the trailer or states the car and the trailer will move as one. B th (1) (1 marks) 4b Award ft marks for a correct answer using their value from part a for the resistance acting on the trailer. 4c Award ft marks for a correct answer using their value from part a for the resistance acting on the trailer and from part b for tension. Education Ltd 017. Copying permitted for purchasing institution only. This material is not copyright free.

5 5a 5b 5c 1 Correctly uses s ut at to write (0) t a (0.8) Correctly finds a = (m s ) or.815 (m s ). Accept awrt.8 (m s ). Demonstrates an understanding that the resultant force acting on sphere B is 1.g T. 45 Uses F = ma to write 1.g T Correctly solves to find T = 1677 (N) or (N). Accept (N). Demonstrates an understanding that the resultant force acting on box A is T F Uses F = ma to write F A1 1.1b () Correctly solves to find F = (N). (N) or (N). Accept A1ft 1.1b Education Ltd 017. Copying permitted for purchasing institution only. This material is not copyright free.

6 5d 45 Uses v = u + at to write v Solves to find v = 9 4 or.5 m s 1. Uses F = ma to write F = 0.8a or = 0.8a M1 3.1b Solves to find a = 17 m s or 7.66 ( m s ). 160 Uses v u as to write s M1.a Solves to find s = 135 (m) or 0.33 (m). Accept awrt (m). States that the total distance travelled will be 1.3 m ( ). B1 ft 3. (7) (15 marks) 5b Award ft marks for a correct answer using their value from part a for acceleration. 5c Award ft marks for a correct answer using their values from part a for acceleration and part b for tension. 5d Award ft marks for a correct answer using their values from parts a, b and c. Education Ltd 017. Copying permitted for purchasing institution only. This material is not copyright free.