1 ) The percentage error in the measurement of mass and speed are 3% and 4% respectively . Then Maximum error in Kinetic energy will be ?
A ) 9% , B ) 11% ,
C ) 15% , D ) None of these ,
Correct Answer : - B ) 11% ,
Solution : -
Formula : -
We have formula for Kinetic energy is : -
K.E = (1/2)m(v^2) ,
But for percentage error , it will write like this : -
∆k/k = (∆m/m) + 2(∆v/v) , OR
∆k/k = 3% + 2(4%) = 11% . Answer .
So percentage error will be 11% .
2 ) If temperature in kelvin scale is reduced to half , then what would be effect on energy of radiations ?
A ) becomes 1/8th , B ) becomes 1/16th ,
C ) becomes 1/32th , D ) None of these ,
Correct Answer : - B ) becomes 1/16th,
Solution : -
3 ) The time period of same pendulum at karachi and murree is related as : -
A ) Tm > Tk , B ) Tm < Tk ,
C ) Tm = Tk , D ) None of these ,
Correct Answer : - A ) Tm > Tk ,
Because time period formula : - T = 2 π√(L/g) ,
So “g” at Karachi is greater than murree : - gk > gm
So by this time period at murree is more than Karachi : - Tm > Tk ,
4 ) Child paradox is a consequence of …………. ( time dilation ) .
5 ) Capacitance in parallel plate capacitor : - C = (AE˳) / d .
When medium is placed in a capacitor : - C = (kAE˳) / d .
6 ) ( Mass spectrometer ) …………. is used to measure the mass of a charge particle .
7 ) The bodies which fall freely under the action of gravity gives : -
A ) non uniform acceleration , B ) uniform acceleration ,
C ) constant acceleration , D ) None of these ,
Correct Answer : - B ) uniform acceleration ,
8 ) A man throws a ball vertically upward in a compartment of an accelerated train . The ball will fall ………… ,
A ) in front of him , B ) behind him ,
C ) may A or B , D ) None of these ,
Correct Answer : - B ) behind him ,
Because an accelerated train will go ahead of the ball and man is in motion with respect to train . And ball is also in motion but with respect to air .
9 ) The geostationary satellites are rotating around ……….. ,
A ) sun , B ) moon ,
C ) earth , D ) None of these ,
Correct Answer : - C ) earth ,
10 ) SI units planks constant : -
A ) Js , B ) J/s ,
C ) J/s2 , D ) None of these ,
Correct Answer : - A ) Js ,
Solution : -
E = h f ,
h = E / f ,
h = J / (s^-1) = Js . Answer .
Now go to online quiz section and Physics Quiz 6 is uploaded related to these mcqs , so check your preparation by this link : -
0 Comments