Experimental investigations show that the intensity of solar radiation is maximum for a wavelength 480 nm in the visible region. Estimate the surface temperature of sun. (Given Wien's constant b = 2.88 x 10-3 mK.)
4000 K
6000 K
8000 K
106 K
The temperature of an ideal gas is increased from 120 K to 480 K. If at 120 K, the root mean square speed of gas molecules is v, then at 480 K, it will be
4v
2v
n identical droplets are charged to V volt each. if they coalesce to form a single drop, then its potential will be
n2/3V
n1/3V
nV
V/n
A particle of mass m is attached to three identical massless springs of spring constant k as shown in the figure. The time period of vertical oscillation of the particle is
A spring of force constant k is cut into three equal parts. The force constant of each part would be
3k
k
2k
A body floats in water with 40% of its volume outside water. When the same body floats in oil, 60% of its volume remains outside oil. The relative density of the oil is
0.9
1.2
1.5
1.8
C.
1.5
A body floats with 40% of its volume outside water, hence fraction of the immersed part
So,in water, f = 1 − 0.4 = 0.6
Hence,
In oil, the body floats with 60% of its volume outside water, hence fraction of the immersed part = f' = 1 − 0.6 = 0.4
So, in oil,
⇒ 0.4 =
A uniform long tube is bent into a circle of radius R and it lies in vertical plane. Two liquids of same volume but densities ρ and δ fill half the tube. The angle θ is
Two solid spheres of same metal but of mass M and 8M fall simultaneously on a viscous liquid and their terminal velocities are v and nv, then value of n is
16
8
4
2
A particle is executing linear simple harmonic motion of amplitude A. At what displacement is the energy of the particle half potential and half kinetic ?
The equation of a progressive wave is where x is in metre and t is in second. The velocity of the wave is