Worksheet for chapter: Work and Energy is presented below. The worksheets are provided for practice and self evaluation of students of class 9. Solutions are provided at the end of the page.
(1) If a force of 10 N applied on an object, it displaced 8 m in the direction of the force applied. Calculate work done on the object.
(2) Define energy?
(3) What does a “unit” means?
(4) An electric bulb of 60 w is used for 3 hours per day. Calculate the “units” of energy consumed in one day y the bulb.
(5) An object of mass 100 kg starts moving at velocity 10 m/s. It velocity increases to 20 m/s. Calculate its kinetic energy?
(6) In which fig given below work done will be greater.
(7) What is the energy transformation in stretched bow and arrow?
(8) There are two children A and B. Both weigh same. They climb a rope of 8 m. Child A completes climbing in 10 second while child B completes climbing in 5 second.
(i) Who has done more work?
(ii) Who has done more work in 1 second?
(9)Find the potential energy of the object whose mass is 18 kg. The object is at the 10 m height. (Take g = 10 m/s2)
(10) A porter carry 10 kg load on its head and stand at a place for half an hour and waiting for the train. Another porter also carry 10 kg load and walk 100 m distance. Which porter has done work and why?