Peoples Physics Concepts

(Marvins-Underground-K-12) #1

8.8. Mechanical Advantage http://www.ck12.org


a. What is the Mechanical Advantage of this crowbar, shown above with its dimensions?
b. How much force is being applied to the wood plank?


  1. A mover loads a 100-kg box into the back of a moving truck by pushing it up a ramp. The ramp is 4 m long
    and the back of the truck is 1.5 m high.
    a. Calculate the potential energy gained by the box when it’s loaded into the truck.
    b. Calculate the mechanical advantage of the ramp.
    c. Calculate the force required to push the box up the ramp in the absence of friction.


Answers


  1. a. M.A. = 12 b. Force out = 360 N

  2. a. 1500 J b. 2.7 c. 375 N


Summary


In these lessons students explore types of energy and the law of energy conservation. Students will also investigate
and calculate power, work and efficiency.
Free download pdf