An object is lifted vertically to a height of 10 m. If the mass of the object is
Practice Questions
Q1
An object is lifted vertically to a height of 10 m. If the mass of the object is 5 kg, what is the work done against gravity?
50 J
100 J
150 J
200 J
Questions & Step-by-Step Solutions
An object is lifted vertically to a height of 10 m. If the mass of the object is 5 kg, what is the work done against gravity?
Correct Answer: 490 J
Step 1: Identify the mass of the object. In this case, the mass is 5 kg.
Step 2: Identify the height to which the object is lifted. Here, the height is 10 m.
Step 3: Know the acceleration due to gravity (g). It is approximately 9.8 m/s².
Step 4: Use the formula for work done against gravity: Work done = mass × g × height.
Step 5: Substitute the values into the formula: Work done = 5 kg × 9.8 m/s² × 10 m.
Step 6: Calculate the result: 5 × 9.8 = 49, then 49 × 10 = 490.
Step 7: Conclude that the work done against gravity is 490 Joules (J).
Work Done Against Gravity – Work done is calculated using the formula W = mgh, where W is work, m is mass, g is acceleration due to gravity, and h is height.
Units of Measurement – Understanding the units involved in the calculation, such as kilograms for mass, meters for height, and joules for work.
