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5 votes
5 votes
If a crane worker lifts a crate with a mass of 120 kg from the ground to a

shipping container that is 30 meters off the ground, by how much has the
worker increased the gravitational potential energy of the crate? (Recall that g
= 9.8 m/s2)
A. 46,720 J
B. 35,280 J
C. 29,950 J
D. 18,180 J
SOEM

User John Hart
by
2.6k points

2 Answers

7 votes
7 votes

Final answer:

The gravitational potential energy increase when a 120 kg crate is lifted 30 meters is calculated using the formula PE = mgh, which results in 35,280 J (option B).

Step-by-step explanation:

The question asks to calculate the increase in gravitational potential energy when a crane worker lifts a crate with a mass of 120 kg to a height of 30 meters. The formula for gravitational potential energy is PE = mgh, where m is mass, g is the acceleration due to gravity, and h is height.

Using the values provided:

Mass, m = 120 kg

Acceleration due to gravity, g = 9.8 m/s2

Height, h = 30 m

We calculate the increase in potential energy as follows:

PE = mgh = 120 kg × 9.8 m/s2 × 30 m = 35,280 J

Therefore, the correct answer is B. 35,280 J.

User Listerone
by
2.8k points
10 votes
10 votes

Answer:

  • A. 88,200 J

Step-by-step explanation:

Given data,

  • mass of the crate, m = 200 kg
  • height of the shipping container, h = 45 m
  • gravitational of a body is possessed by the body due to the virtue of its position.

The formula for gravitational potential energy is,

P.E = mgh joules

Substituting the values

P.E = 200 x 9.8 x 45

= 88,200 J

Hence, the gravitational potential energy of the crate is, P.E = 88,200 J

User Alex Peattie
by
3.1k points