What Do You Know About Forces?

1. A very thin person wants to lift him or herself up to the third floor window of their house (to paint/clean windows, etc.). This person asks you for your wise technical advice in deciding whether any of the following schemes will work.
   1. 
      1. Will it work?
      2. Will he hurt?

   2. 
      1. Will it work?
      2. Will he hurt?

   3. 
      1. Will it work?
      2. Will he hurt?

   ---

2. Below is a movie of a car and truck crashing together.
   Is the force the car exerts on the truck
   1. greater than the force the truck exerts on the car
   2. less than the force the truck exerts on the car
   3. equal to the force the truck exerts on the car
   4. impossible to determine without knowing the speeds of the car and the truck

   ---

3. Why does a balloon filled with gas go up?
   

   ---

4. One block of mass A (15 kg) is constantly in contact with another block of mass B (10 kg). If block A is being pushed by a force of 5 newtons, find
   
   1. The acceleration and magnitude of forces acting on block A.
   2. The acceleration and magnitude of forces acting on block B.

   The free-body diagram describing all forces must be as shown below:
   

   ---