Answer:
Option a
Explanation:
The action of the rapid rubbing of the hands are a result of chemical reaction and responses that takes place inside our body.
When we rub our hands together, that shows the mechanical motion of the body or we can say that while rubbing hands chemical energy gets converted to mechanical energy (here, Kinetic energy).
While rubbing, due to friction, heat is produced and hence we can say that this mechanical energy has transformed to heat energy.
Thus the conversion here is from chemical to mechanical to heat energy.
Force on a moving charge is given by formula

here we know that this force will be maximum when velocity is perpendicular to magnetic field

here we know that



now we have


Answer:
it's is because the heavier the object is the more it will be pulled down by gravity n the lighter the object the lesser the gravity will pull it down
The answer is D) absorb most of the light that falls on them
A blackbody is an object that absorbs most (theoretically all) of the light that falls on it. Stars are called black bodies because they demonstrate something close to this property. Why do they appear white and not black? As black body radiators heat up, they slowly turn from black to grey to white, according to the human eye. Since stars are incredibly hot, they appear white to us.
If both bars are made of a good conductor, then their specific heat capacities must be different. If both are metals, specific heat capacities of different metals can vary by quite a bit, eg, both are in kJ/kgK, Potassium is 0.13, and Lithium is very high at 3.57 - both of these are quite good conductors.
If one of the bars is a good conductor and the other is a good insulator, then, after the surface application of heat, the temperatures at the surfaces are almost bound to be different. This is because the heat will be rapidly conducted into the body of the conducting bar, soon achieving a constant temperature throughout the bar. Whereas, with the insulator, the heat will tend to stay where it's put, heating the bar considerably over that area. As the heat slowly conducts into the bar, it will also start to cool from its surface, because it's so hot, and even if it has the same heat capacity as the other bar, which might be possible, it will eventually reach a lower, steady temperature throughout.