Answer:

Explanation:
In order to solve this problem, we can do an analysis of the energies involved in the system. Basically the addition of the initial potential energy of the spring and the kinetic energy of the mass should be the same as the addition of the final potential energy of the spring and the kinetic energy of the block. So we get the following equation:

In this case, since the block is moving from rest, the initial kinetic energy is zero. When the block loses contact with the spring, the final potential energy of the spring will be zero, so the equation simplifies to:

The initial potential energy of the spring is given by the equation:

the Kinetic energy of the block is then given by the equation:

so we can now set them both equal to each other, so we get:

This new equation can be simplified if we multiplied both sides of the equation by a 2, so we get:

so now we can solve this for the final velocity, so we get:

Given gravitational potential energy when he's lifted is 2058 J.
Kinetic energy is transferred to the person.
Amount of kinetic energy the person has is -2058 J
velocity of person = 7.67 m/s².
<h3>
Explanation:</h3>
Given:
Weight of person = 70 kg
Lifted height = 3 m
1. Gravitational potential energy of a lifted person is equal to the work done.

Gravitational potential energy is equal to 2058 Joules.
2. The Gravitational potential energy is converted into kinetic energy. Kinetic energy is being transferred to the person.
3. Kinetic energy gained = Potential energy lost = 
Kinetic energy gained by the person = (-2058 kg.m/s²)
4. Velocity = ?
Kinetic energy magnitude= 
Solving for v, we get

The person will be going at a speed of 7.67 m/s².
Answer:
The answer is 2,416 m/s. Let's jump in.
Explanation:
We do work with the amount of energy we can transfer to objects. According to energy theory:
W = ΔE
Also as we know W = F.x
We choose our reference point as a horizontal line at the block's rest point.<u> At the rest, block doesn't have kinetic energy</u> and <u>since it is on the reference point(as we decided) it also has no potential energy.</u>
Under the force block gains;
W = F.x → 
In the second position block has both kinetic and potential energy. Following the law of conservation of energy;
W = ΔE = Kinetic energy + Potantial Energy
W = ΔE = 
Here we can find h in the triangle i draw in the picture using sine theorem;
In a triangle 
In our situation
→ 
Therefore

→ 
Gravitational, gravitational ! both the option are same