1.1. Fig. 2.1 shows an athlete crossing the finishing line in a race. As she crosses the finishing line, her speed is 10.0 m/s. She slows down to a speed of 4.0 m/s.      

The mass of the athlete is 71 kg. Calculate the impulse applied to her as she slows down. 

 impulse = ............................................... 

1.2. (i) Define impulse in terms of force and time.

[1]

(ii) The athlete takes 1.2 s to slow down from a speed of 10.0 m/s to a speed of 4.0 m/s.

Calculate the average resultant force applied to the athlete as she slows down.

  force = ........................................................ [2]

1.3. Calculate the force required to give a mass of 71 kg an acceleration of 6.4 m/s².

  force = ........................................................