Mechanical Systems

Simple machines, how force and energy transfer through a system, and mechanical advantage.

8 questions, free, marked as you go with a worked explanation on every one.

What this covers

• mechanical systems
• energy efficiency

The questions

1. A machine outputs 200 N of force when 50 N is applied to it. What is its mechanical advantage?
2. Which of these is a simple machine?
3. A lever multiplies your force. What do you give up in exchange?
4. A machine is supplied with 200 J and delivers 60 J of useful work. What is its efficiency as a percentage?
5. Why is no machine 100% efficient?
6. Which are ways a mechanical system transfers force or energy? Select all that apply.
7. A caretaker pushes a loaded cart down a hallway with a steady horizontal force of 45 N, moving it 12 metres in the direction of the push. How much work does he do on the cart, in joules?
8. A mechanic uses a hydraulic jack to lift a car. A small force on the narrow piston produces a much larger force at the wide piston. Why does this work?

Answer these free