Answer:
During a typical school day all forms of eneergy is being utilised and also transfer of energy takes place from one form to another.
Explanation:
Chemical energy- A bunsen burner burning a beaker filled with water.
Heat energy- The water in the beaker absorbing the heat from the burner.
Electrical energy- Running Fans and lights in a classroom by switches.
Solar energy- Solar energy harnessed by solar panels to run the fans and lights by converting it into electrical energy.
Potential energy- A ball being held by a student at a certain height possesses energy due to gravity.
Kinetic energy- The same ball being left by the boy from a certain height produces kinetic energy
The answer is A. The Sun and all the planets revolve around Earth.
Aristotle believed that the Earth was the centre of the solar system, and the Sun and the planets orbited around it. He believed that the universe was composed of Earth-like bodies, which were at rest, and of heavenly bodies, which were in perpetual motion.
Answer:
Kinetic energy is 1425.11 J.
Explanation:
Given:
Mass of the wrench is,
Height of fall is,
Force of resistance is,
Now, the total energy at the top is equal to the potential energy of the wrench at the top since the kinetic energy at the top is 0.
Now, potential energy at the top is given as:
Now, the potential energy at the top is converted to kinetic energy at the bottom and some energy is wasted in overcoming the resistance force by air.
Potential Energy = Kinetic energy + Energy to overcome resistance.
⇒ Kinetic energy = Potential Energy - Energy to overcome resistance.
Energy to overcome resistance force is the work done by the wrench against the resistance force and is given as:
Therefore, Kinetic energy at the bottom is given as:
Hence, the kinetic energy of the wrench be when it hits the water is 1425.11 J.
Answer: The major challenges are as
1) understanding of the plasma: Plasma is a soup like mixture of subatomic particles of different atoms nuclei and electrons that are shattered apart by the temperature at which plasma is formed. further research is needed to understand the behavior of plasma so that it can be put to a proper use.
2) Confinement of plasma: Once we get the plasma we need to hold it so that we can obtain heat from it to drive a steam turbine but the sheer temperature of plasma is in millions of Celsius thus currently making it impossible to confine conventionally. Scientists use a loop of electric and magnetic fields to keep it in circulatory like manner so that it can be studied.
3) finally to obtain electricity from the plasma it should be stable to produce electricity. But currently to obtain pressure, temperature so that we have a sustained supply is highly difficult in technical and economical aspects.
Inertial confinement: In order to get the nuclei of atoms close enough for fusion this type of method used compression of the nuclei into highly small volumes.This is accomplished by use of lasers which are directed towards the fuel pellets that implode and travel towards other nuclei making fusion possible. It's main advantage is that it requires lesser time to initiate fusion but the disadvantage being that a large power is used to fire the lasers and the lasers should all hit the small target.
Magnetic Confinement: In this method we use a magnetic and electric fields in a properly designed space to keep the plasma in motion. In motion the nuclei of the atoms come close enough to initiate fusion.It's advantage being less power is required to start the process as compared to inertial confinement and the disadvantage being that plasma confinement is currently not properly understood.
Answer:
Explanation:
We can use the following SUVAT equation to solve the problem:
where
v = 0 is the final velocity of the car
u = 24 m/s is the initial velocity
a is the acceleration
d = 196 m is the displacement of the car before coming to a stop
Solving the equation for a, we find the acceleration: