Answer: Our body contains chemical potential energy from food we have eaten.
This chemical potential energy is transformed into the kinetic energy of our hands and arms as we rub our hands together.
As our hands move past each other and rub against each other, friction allows the kinetic energy to be transformed into thermal energy on the surface of our hands.
Explanation:
It is true that our food contains chemical bonds and these bonds have potential energy stored. So, when we eat food then our body acquires chemical potential energy.
When we rub our hands and arms then they form kinetic energy as atoms present within the skin of our hands come into motion. This rubbing of hands leads to the formation of heat which means thermal energy is being generated.
Thus, we can conclude that our body contains chemical potential energy from food we have eaten.
This chemical potential energy is transformed into the kinetic energy of our hands and arms as we rub our hands together.
As our hands move past each other and rub against each other, friction allows the kinetic energy to be transformed into thermal energy on the surface of our hands.
Answer:
Because of the formula
Explanation:
In this problem we are describing two different processes:
- Nuclear fission occurs when a heavy, unstable nucleus breaks apart into two or more lighter nuclei
- Nuclear fusion occurs when two (or more) light nuclei fuse together producing a heavier nucleus
In both cases, the total mass of the final products is smaller than the total mass of the initial nuclei.
According to Einsten's formula, this mass difference has been converted into energy, as follows:
where:
E is the energy released in the reaction
is the mass defect, the difference between the final total mass and the initial total mass
is the speed of light
From the formula, we see that the factor is a very large number, therefore even if the mass defect is very small, nuclear fusion and nuclear fission release huge amounts of energy.
Answer:
Explanation:
Notice that this is a circuit with resistors R1 and R2 in parallel, connected to resistor R3 in series. It is what is called a parallel-series combination.
So we first find the equivalent resistance for the two resistors in parallel:
By knowing this, we can estimate the total current through the circuit,:
So approximately 0.17 amps
and therefore, we can estimate the voltage drop (V3) in R3 uisng Ohm's law:
So now we know that the potential drop across the parellel resistors must be:
10 V - 4.28 V = 5.72 V
and with this info, we can calculate the current through R1 using Ohm's Law: