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The work done in an isothermal expansion of a gas depends upon:
The work done in an isothermal expansion of a gas depends upon both temperature and expansion ratio.
The work done in an isothermal process is given by:
W=nRTln(V1V0)⇒W∝T,ln(V1V0)
V1 and V0 are the final and initial volumes respectively, thus it represents the change in volume during expansion. Therefore, work done in an isothermal change of a gas depends on both the temperature and volume expansion ratio.
In a potentiometer arrangement, a cell gives a balancing point at 75 cm length of wire. This cell is now replaced by another cell of unknown emf. If the ratio of the emf's of two cells respectively is 3:2, the difference in the balancing length of the potentiometer wire in above two cases will be __cm.
At balancing point, we know that emf is proportional to the balancing length. i.e., emf ∝ balancing length
Now, let the emf's be 3ε and 2ε.
⇒3ε=k(75)…..(1)
and 2ε=k(I)…..(2)
⇒I=50 cm
⇒ Difference is (75−50)cm=25 cm.
If a material have less specific heat then it means that ________.
If a material have less specific heat then it means that less amount of energy is needed to increase its temperature.
The specific heat capacity (S) of a substance is defined as the amount of heat (ΔQ) per unit mass of the substance that is required to raise the temperature
(ΔT) by 1∘ C
i.e., S=ΔQmΔT
And the unit of Specific heat is J/g∘ C and Cal/g∘ C
Here,
S= specific heat of material
ΔQ= heat exchange
ΔT= change in temperature
m= unit mass of material
Thus, if specific heat of a material is less it means that the less amount of energy is needed to increase its temperature.
When an object is oscillating in simple harmonic motion in the vertical direction, its maximum speed occurs when the object:
When an object is oscillating in simple harmonic motion in the vertical direction, its maximum speed occurs when the objecthas the maximum net force exerted on it.
Because the total energy is fixed at kA22, the maximum kinetic energy occurs at the minimum potential energy, where x=0.
Thus, the maximum speed is at the equilibrium position.
A force of 12 N displaces a body by 60 cm in its direction. The work done on the body will be:
Given that:
Force (F) = 12 N
Displacement (s) = 60 cm = 60100 = 0.6 m
The force (F) and displacement (s) are in the same direction, so θ = 0°
Work done = Fs cos θ = 12 × 0.6 × 1 = 7.2 J
Rutherford's α-particle experiment showed that the atoms have:
In Rutherford's alpha particle experiment, the scattered alpha particle has large deflection angles. This experiment showed that the positive matter of atom was concentrated in an very small volume and it gave the idea of nucleus of an atom.
In a p-type semiconductor hole are the majority carriers and electrons are the minority carriers. It is obtained by using a trivalent dopant.
The electromagnetic waves can be produced by:
The property of matter which is responsible for electromagnetic phenomenon is called charge. The space or region around the current carrying wire/moving electric charge or around the magnetic material in which force of magnetism can be experienced by other magnetic material is called as magnetic field/magnetic induction by that material/current. The space or region around the electric charge in which electrostatic force can be experienced by other charge particle is called as electric field by that electric charge.
A body of density ρ is dropped from rest from a height h into a lake of density σ(σ>ρ). The maximum depth the body sinks inside the liquid is (neglect viscous effect of liquid):
The velocity of body just before touching the lake surface is:
v=2gh
Retardation in the lake:
a= upthrust-weight a
⇒Vρg−VρgVρ=(σ−ρρ)g
Maximum depth dmax=v22a
⇒hρσ−ρ
If an electron and a proton having the same momenta enter perpendicular to a magnetic field, then
The length of curved path or orbital radius,
R=mVqB=pqB
Where,
m = Mass
V = Velocity
Q = Charge
B = Magnetic field
p = Momentum
Since p remains the same for both,
Re=peB
Rp=peB
∴Rv=Rp
By the above expression this is proved, the length of curved path of electron and proton will be same.
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