Question

How far will 350 J raise a 70 Newton block?

Answer 1

Hint : Weight is defined as the measure of the force of gravity acting on the object. In weight, changes occur only when mass and gravity changes.

Complete Step by step solution:
Given data:
Weight = 70 N
Distance, d =?
According to the principle of the conservation of energy, the work done by lifting the block is equal to its increase in the gravitational potential energy.
The gravitational potential energy is defined as the energy that is stored in an object as a result of its vertical position and the energy stored is the result of the gravitational attraction of the Earth for an object.
Mathematically, it is given by,
\[GPE = mgd\]
Where GPE is the gravitational potential energy, m is the mass of the block, g is the acceleration due to gravity and d is the distance.
Thus, \[GPE = Wd\] $\left( {\because W = mg} \right)$
Substituting the values, we get,
$350 = 70 \times d$
$ \Rightarrow d = \dfrac{{350}}{{70}} = 5m$
Hence the distance, d = 5m

Note:
1. A book on a table before it falls, A raised weight, Ripe fruit before it falls, A child at the top of a slide are some of the examples of the gravitational potential energy.
2. Mass, gravity and height are the three factors by which gravitational potential energy can be determined.
3. The higher the object the greater is the gravitational potential energy. Thus, the change in the gravitational potential energy depends on the mass of the object that is changing with the height.
4. The gravitational potential energy is minimum at the surface of the earth. It decreases continuously from infinity to the surface of the earth.