Answer:
white star
Explanation:
because it is the hottest form of a star
Answer:
A. Their same forces repel each other, and their opposite forces attract each other.
Explanation:
As we know by the property of electric charge that similar charges repel each other and opposite charges attracts each other
So here we have similar situation in magnets also
Two similar poles or like poles of magnet i.e. North - North poles or South - South poles always repel each other
And also we can see that opposite poles of magnet each other i.e. North pole and south pole always attract each other.
SO here correct answer is
A. Their same forces repel each other, and their opposite forces attract each other.
Answer:
At 81. 52 Deg C its resistance will be 0.31 Ω.
Explanation:
The resistance of wire =
Where 
=Resistance of wire at Temperature T
= Resistivity at temperature T ![=\rho_0 \ [1 \ + \alpha\ (T-T_0\ )]](https://tex.z-dn.net/?f=%3D%5Crho_0%20%5C%20%5B1%20%5C%20%2B%20%5Calpha%5C%20%28T-T_0%5C%20%29%5D)
Where 
l=Length of the wire
& A = Area of cross section of wire
For long and thin wire the resistance & resistivity relation will be as follows
![\frac{0.25}{0.31}=\frac{1}{[1+\alpha(T-20)]}](https://tex.z-dn.net/?f=%5Cfrac%7B0.25%7D%7B0.31%7D%3D%5Cfrac%7B1%7D%7B%5B1%2B%5Calpha%28T-20%29%5D%7D)
T = 81.52 Deg C
When a small cart collide with a large mass then during collision they must be in contact with each other for some interval of time
During this contact interval we can say they will exert normal force on each other
This normal force is always equal and opposite on two balls which means this force will follow Newton's III law
It will be same in magnitude but opposite in the direction
So here correct answer would be
<u><em>They both experience the same magnitude of the collision force.</em></u>
