3. an object of mass 5.0 kg is lifted vertically upward by 2.0 m. assuming the acceleration due to gravity…

3. an object of mass 5.0 kg is lifted vertically upward by 2.0 m. assuming the acceleration due to gravity is $9.8\\ \\text{m/s}^2$, how much work is done against gravity?\na. 10 j\nb. 20 j\nc. 49 j\nd. 98 j
Answer
Explanation:
Step1: Calculate gravitational force
$F = m \times g = 5.0\ \text{kg} \times 9.8\ \text{m/s}^2 = 49\ \text{N}$
Step2: Calculate work against gravity
$W = F \times d = 49\ \text{N} \times 2.0\ \text{m} = 98\ \text{J}$
Answer:
D. 98 J