A magnet is similar to a bipolar charged system in that
it consists of two opposite poles - the north and south poles
the earth's magnetic field has a south pole near the geographical north pole and a north pole near the geographical south pole
the force of attraction and repulsion between opposite and between like poles obeys a law for electrostatic charges
A and B only
A and C only
Correct answer is E
No explanation has been provided for this answer.
Which of the following statements are true in the structure of atoms?
the atoms of the differnt element differ only in the number of protons and electrons
the num,ber of protons equals the number of electrons
atoms are constructed according to the plan of our solar system
all of the above
A and C only
Correct answer is B
No explanation has been provided for this answer.
Which of the following is true of an electrical charge?
positive charge means deficit electrons
negative charge means excess of electrons
electric current means movement of electrons
all of the above
A and B only
Correct answer is D
No explanation has been provided for this answer.
Which of the following statements are true of the law of universal gravitation?
any two bodies attract each other with a force which is proportional to the difference of their masses
any two bodies attract each other with a force which is inversely proportional to the square of the distance between them
any two bodies attract each other with a force which is proportional to the product of their masses and inversely proportional to the square of the distance between them
any two bodies attract each other with a force which is proportional to the square of the distance between them
any two bodies attract each other with a force which is proportional to the sum of their masses
Correct answer is C
No explanation has been provided for this answer.
12
3
2
\(\frac{3}{2}\)
\(\frac{5}{4}\)
Correct answer is B
Relative density of solid = \(\frac{\text{weight of solid}}{\text{weight of an equal volume of water}}\)
\(\frac{4.8}{4.8 -3.2}\) = \(\frac{4.8}{2}\) = 2.4
Ratio of density of liquid = \(\frac{\text{weight of liquid kerosine}}{\text{weight of an equal volume of water}}\)
= \(\frac{4.8 - 3.2}{4.8 - 2.8}\) = \(\frac{1.6}{2}\)
= 0.8
= \(\frac{\text{density of solid}}{\text{density of kerosine}}\)
= \(\frac{2.4}{0.8}\) = 3