1 ) A wire of resistance R is cut into two equal parts . Then two parts are joined in parallel . What would be resistance ?
A ) R/2 , B
) R/4 ,
C ) 2R , D
) None of these ,
Correct
Answer : - B ) R/4 ,
Solution
: -
As we know that resistance
is directly related to the length of a wire .
Ø R α L ,
Ø So
, R/2 α L/2 ,
So resistance in parallel : -
Ø 1/Rp
= 1/R1 + 1/R2 ,
Ø 1/Rp
= 1/(R/2) + 1/(R/2) ,
Ø 1/Rp
= 2/R + 2/R ,
Ø 1/Rp
= 4/R ,
Ø Rp
= R/4 ,
Answer .
2
) Formula for viscosity : - È = F / rv .
3 )
Phase angle in SHM is used to specify ………… of the motion .
A ) displacement , B ) direction ,
C ) both , D
) None of these ,
Correct
Answer : - C ) both ,
4 )
The number of loops in stationary waves depends on …………. of waves .
A ) velocity , B ) frequency
,
C ) wavelength , D
) None of these ,
Correct
Answer : - B ) frequency ,
5 ) ……………
will not changes , when light changes the medium eg . from rare to denser or
vice versa .
A ) velocity , B
) wavelength ,
C ) frequency , D
) None of these ,
Correct
Answer : - C ) frequency ,
6 ) The
power of objective and eye piece of telescope is 0.5 diopter and 10 diopter respectively
. Then magnifying power of telescope
will be ?
A ) 0.05 , B ) 0.5 ,
C ) 5 , D ) None of these ,
Correct
Answer : - A ) 0.05 ,
Solution
: -
7
) A wire of resistance R is cut into
three equal parts . Then these three parts are joined in series . What would be
resistance ?
A ) 1R , B ) 3R
,
C ) R/3 , D )
None of these ,
Correct
Answer : - A ) 1R ,
Solution
: -
So each wire will become R/3 .
So Rs = R1 + R2 + R3 ,
Rs = R/3 + R/3
+ R/3 .
Rs = 3R/3 = R ,
Answer .
8 )
Two metallic conductors have the same value of resistivity . These conductors
are differentiable by their …………….. ,
A ) resistance , B ) inductance ,
C ) conductance , D ) None of these ,
Correct
Answer : - C ) conductance ,
9
) If current flows in same direction ,
so wires will ………… each other .
A ) attract , B
) repel ,
C ) neither attract nor repel , D ) None of these ,
Correct
Answer : - A ) attract ,
10
) The strength of magnetic field around
a solenoid can be increased by : -
A ) increasing the current ,
B ) increasing no.
of turns ,
C ) placing an iron core inside the solenoid ,
D ) All of these ,
Correct
Answer : - D ) All of these ,
11
) The conversion of AC to DC is known as
: -
A ) modulation , B ) rectification ,
C ) amplification , D
) None of these ,
Correct
Answer : - B ) rectification ,
Now go to online quiz section and Physics Quiz 7 is uploaded related to these mcqs , so check your preparation by this link : -
