JAMB Physics 2012 Objective — Question 14
Question 14 of 50 from the Joint Admissions and Matriculation Board (JAMB) Physics 2012 Objective paper, with the correct answer and a full explanation.
Advertisement
A block and tackle is used to raise a load of 250N through a vertical distance of 30m. What is the efficiency of the system if the work done against friction is 1500J?
- A. 62.5%
- B. 73.3%
- C. 83.3%Correct
- D. 94.3%
Explanation
Work done by load (useful work) = 250×30 = 7500J. Total work done by effort = 7500+1500 = 9000J. Efficiency = (7500/9000)×100% = 83.3%.
Advertisement
Sign up free to unlock
- Score tracking
- Practice history
- Saved questions
- Progress dashboard
- Personalized sessions
- Weak-topic breakdown
…and/or go further with premium services and No Ads.