Browse Momentum

35 questions at your level, grouped by concept

  1. 1
    Figure 21.25 mA (0.6 kg)B (0.9 kg)Diagram not accurately drawn.

    Two small blocks, AA of mass 0.60.6 kg and BB of mass 0.90.9 kg, rest 1.251.25 m apart on a rough horizontal floor, as shown in Figure 2. The blocks are modelled as particles.

    The coefficient of friction between each block and the floor is 27\frac{2}{7}

    A sharp blow gives AA an impulse of 2.42.4 N s, directed towards BB, and AA starts to slide across the floor.
    (a) Find the speed with which AA starts to slide.

    (2 marks)
    (b) Show that AA reaches BB with speed 3 m s−13\text{ m s}^{-1}

    (5 marks)

    In the collision, AA and BB join together and move as a single particle.
    (c) Find the speed of the combined particle immediately after the collision.

    (2 marks)
    (d) Find the magnitude of the impulse exerted on AA by BB in the collision, stating the units of your answer.

    (2 marks)
    (e) Find the distance travelled by the combined particle after the collision until it comes to rest.

    (3 marks)
    Level 5 · 14 marksTry it
  2. 2
    A particle AA of mass 3m3m moving with speed uu collides directly with a stationary particle BB of mass mm. After the collision AA continues in the same direction with speed u2\dfrac{u}{2}.
    (a) Find the speed of BB after the collision, in terms of uu. (4 marks)
    (b) Explain why the particles do not collide again. (1 mark)
    Level 5 · 5 marksTry it