Distinguish between work energy and power if a body of weight 10N is lifted from the floor to a table 2m above the calculate the potential energy gained. What happens to the energy if the body falls off the table and hits the floor
work = Force * distance in direction of force
In this case:
work = 10 Newtons up * 2 meters up = 20 Joules of work done
power in Joules = 20 / number of seconds it took
It gained 20 Joules of potential energy going up
During the fall it loses the potential energy but gains an equal amount of Kinetic energy
(1/2) m v^2 = 20 Joules
HOWEVER, when it hits the floor that 20 Joules is lost to heat and to moving floor planks around.
power in Joules = 20 / number of seconds it took
WHOOPS TYPO
power in *** WATTS*** = 20 / number of seconds it took
watts power is Joules of energy per seccond
I must learn to read what I wrote before hitting that button!
To distinguish between work, energy, and power, let's first understand their individual definitions:
1. Work: In physics, work is defined as the product of force and displacement. When a force is applied to an object and the object moves in the same direction as the force, work is said to be done.
2. Energy: Energy is the ability to do work or cause a change. It exists in several forms, such as mechanical energy, potential energy, kinetic energy, thermal energy, etc.
3. Power: Power is the rate at which work is done or energy is transferred. It measures how quickly work is accomplished or energy is converted.
Now let's calculate the potential energy gained by lifting a 10N body from the floor to a table 2m above:
Potential energy (PE) is given by the formula: PE = mgh, where m represents the mass of the body, g represents the acceleration due to gravity (approximately 9.8 m/s^2), and h represents the height.
Given that the weight of the body is 10N, which is equal to the force due to gravity, we can calculate the mass of the object using the formula: weight = mg.
Therefore, m = weight/g = 10N / 9.8 m/s^2 ≈ 1.02 kg.
Now we can calculate the potential energy gained:
PE = mgh = 1.02 kg * 9.8 m/s^2 * 2m = 19.92 Joules.
So, the potential energy gained by lifting the body to the table is approximately 19.92 Joules.
Now, let's discuss what happens to the energy if the body falls off the table and hits the floor:
When the body falls off the table and hits the floor, its potential energy is converted into kinetic energy. As the body falls, gravity accelerates it, increasing its speed and kinetic energy. At the same time, as the body loses height, its potential energy decreases.
When the body hits the floor, some of its kinetic energy is dissipated as sound and heat due to the impact, resulting in a decrease in total mechanical energy.
Therefore, the potential energy of the body is completely converted into kinetic energy while falling, and some of it is lost as heat and sound upon hitting the floor.