CALCULATIONS INVOLVING WORK DONE

CONTENT

Calculations Involving Work Done

1. What work is done when a mass of 5.00kg is raised through a vertical height of 2.5m (acceleration due to gravity is 10m/sec)?

Solution:

Work done = mass × acceleration × distance

Since force = mass × acceleration

W (d) = mass × accel. × distance

= 5.00kg × 10m/s² × 2.5m

= 125 joules

2. Calculate the work-done by a body of weight 200N which, moves through a distance of 12N

Solution:

Force = 200N

Distance moved = 12m

Work done = force × distance moved

= (20012) joules

= 2400 joules.

3. Find the work done by a man who lifts a weight of 20N from the ground to a vertical height of 4m by means of a rope.

Solution:

W = ? F = 20N, S = 4m

W = F × S

W = 20 × 4 = 80 Joules (80J).

You are viewing an excerpt of this lesson. Subscribing to the subject will give you access to the following:

NEW: Download the entire term's content in MS Word document format (1-year plan only)
The complete lesson note and evaluation questions for this topic
The complete lessons for the subject and class (First Term, Second Term & Third Term)
Media-rich, interactive and gamified content
End-of-lesson objective questions with detailed explanations to force mastery of content
Simulated termly preparatory examination questions
Discussion boards on all lessons and subjects
Guaranteed learning