1 )
A body of mass 5 kg is moving with a momentum of 10 kg m / s . A force of 0.2 N
acts on it in the direction of motion of body for 10 secs . The increase in its
kinetic energy is : -
A ) 1.39 J , B
) 4.45 J ,
C ) 9.84 J , D
) None of these ,
Correct
Answer : - B ) 4.45 J ,
Solution
: -
2 )
What will be the duration of day and night ( in hour ) , if the diameter of
earth is suddenly reduced to half of its original value , the mass remaining
constant ?
A ) 2 , B
) 6 ,
C ) 14 , D
) None of these ,
Correct
Answer : - B ) 6 ,
Solution : -
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3 )
If momentum is increased by 20 % , then kinetic energy increases : -
A ) 11 % , B
) 22 % ,
C ) 44 % , D
) None of these ,
Correct
Answer : - C ) 44 % ,
Solution : -
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