1.) What is a second class lever?

2.) What is a third class lever?

3.) What is mechanical advantage?

4.) What is velocity ratio?

5.) Why do MA and VR do not have unit?

6.) What is efficiency of a machine?

7.) What is output work?

8.) What is input work?

9.) What are ideal machines?

10.) What are simple machines?

11.) What is input and output?

12.) What is input and output?

13.) What are the advantages of simple machines?

14.) What are the types of simple machines?

15.) What is the principle of simple machine?

16.) What is a lever?

17.) What is load? What is an effort?

18.) What is load distance? What is effort distance?

19.) What are the types of lever?

20.) Differentiate between: a)mechanical advantage and velocity ratio b)input work and output work

21.) Give reasons: (i) The efficiency of the l ever is never 100 %. (ii) It is easier to push the load in a wheelbarrow while shifting the load towards its wheel. (iii) Mechanica l advantage is always less than the velocity ratio.

22.) Answer the following questions: (i) How can we lift the heavy load by using a lever? (ii) Which class lever is a scissor? (iii) What can be done with a lever whose mechanical advantage is more than 1? (iv) What are the other advantages of lever besides in

23.) Solve these numerical problems: (i) An effort of 75 N is required to lift the load of 300 N. Calculate the effort distance if the distance of the l oad from the fulcrum is 25 cm. (Ans: 100 cm) (ii) The weight of Sarad is 550 N and Nirmal is 300 N. Sarad