Assertion: Frictional forces are conservative forces.
Reason: Potential energy can be associated with frictional forces.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false
Assertion: : For a system of particles under central force field, the total angular momentum is conserved.
Reason: The torque acting on such a system is zero.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false
For a constant hydraulic stress on an object, the fractional change in the object's volume ( ΔV/V ) and its bulk modulus (B) are related as
Which of the following functions represents a simple harmonic oscillation?
sinωt cosωt
sin2ωt
sinωt + sin2ωt
sinωt sin2ωt
A candle of diameter d is floating on a liquid in a cylindrical container of diameter D ( D >> d ) as shown in figure. If it is burning at the rate of 2 cm/hour then the top of the candle will
remain at the same height
fall at the rate of 1 cm/hour
fall at the rate of 2 cm/hour
go up at the rate of 1 cm/hour
A given shaped glass tube having uniform cross section is filled with water and is mounted on a rotatable shaft as shown in figure. If the tube is rotated with a constant angular velocity ω when
water levels in both sections A and B go up
water level in section A goes up and that in B comes down
water level in section A comes down and that in B it goes up
water levels remain same in both sections
A.
water levels in both sections A and B go up
Due to rotation about the OO', a force is acting on the liquid column AB outwards, pushing up the liquid column AB outwards, pushing up the liquid column on the right. This centrifugal force acting on the small element 'dx' of area cross-section 'dx', distant x from the axis is
dm ω2x = A dx ρω2x
The total force due to the column of length L ( = AB ) is
Aρω2 · x dx = A ρω2
Pressure at B = atmospheric pressure + h1ρg +
Pressure at B due to liquid colomn on the right hand side
= atmospheric pressure + h2ρg
Net pressure due to the left-hand side = pressure at B due to liquid column
atm. pressure + h1ρg + ρω2 = atm. pressure + h2ρg
∴ h2 h1 = H0 =
Here one has
H2 =
H1 =
As ω is the same, and L2 > L1, H2 > H1
But both will go up.
A magnet is made to oscillate with a particular frequency, passing through a coil as shown in figure. The time variation of the magnitude of e.m.f. generated across the coil during one cycle is
Assertion: Specific gravity of a fluid is a dimensionless quantity
Reason: : It is the ratio of density of fluid to the density of water.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false
Assertion: Reversible systems are difficult to find in real world.
Reason : Most processes are dissipative in nature.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false