Correct Answer: Option C

Explanation

Efficiency = \(\frac{output}{input}\) x 100

40 = \(\frac{20\times10}{input}\) x \(\frac{100}{1}\)

input = 500J

work against friction = input - output

= 500 - 200 = 300J

• If the power of a lens is +2.5D. Calculate the radius of curvature (a). 80cm (b). 40cm (c). 25cm (d).... Answer this

  1 Answers   ·   Physics   ·   3 days ago
• Subjects to learn under petroleum engineering? Answer this

  1 Answers   ·   2 days ago
• what is the cut of mark for medical doctor in university and list all the university? Answer this

  1 Answers   ·   21 hours ago