A man of mass 50kg ascends a flight of stains 5m high in 5 seconds. If acceleration due to gravity is 10ms\(^{-2}\) the power expended is
Question 1 Report
A man of mass 50kg ascends a flight of stains 5m high in 5 seconds. If acceleration due to gravity is 10ms\(^{-2}\) the power expended is
Answer Details
To find the power expended, we can use the formula:
power = force × velocity
Since the man is ascending the stairs at a constant speed, the net force acting on him is zero. However, he is working against the force of gravity, which is pulling him downward with a force equal to his weight, given by:
force = mass × acceleration due to gravity = 50 kg × 10 m/s^2 = 500 N
The velocity of the man can be found from the distance he covers and the time taken:
velocity = distance/time = 5 m/5 s = 1 m/s
Thus, the power expended by the man is:
power = force × velocity = 500 N × 1 m/s = 500 watts
Therefore, the correct answer is option D: 500w.
Download The App On Google Playstore
Everything you need to excel in your exams
Personalized AI Learning Chat Assistant
200,000+ Exam Questions Across IGCSE, JAMB, WAEC & NECO
Over 3,900 Lesson Notes
Offline Support - Learn Anytime, Anywhere
Green Bridge Timetable
Literature Summaries & Potential Questions
Track Your Performance & Progress
In-depth Explanations for Comprehensive Learning