The magnetic field in a plane electromagnetic wave is By=(3.5×10−7)sin(1.5×103x+0.5×1011t)T. The corresponding electric field will be :
Physicselectromagnetic-waves2024medium
A plane EM wave is propagating along x direction. It has a wavelength of 4mm. If electric field is in y direction with the maximum magnitude of 60Vm−1, the equation for magnetic field is :
Physicselectromagnetic-waves2024easy
The electric field in an electromagnetic wave is given by E=i^40cosω(t−z/c)NC−1. The magnetic field induction of this wave is (in SI unit) :
Physicselectromagnetic-waves2024easy
Arrange the following in the ascending order of wavelength:
A. Gamma rays (λ1)
B. x - rays (λ2)
C. Infrared waves (λ3)
D. Microwaves (λ4)
Choose the most appropriate answer from the options given below
Physicselectromagnetic-waves2024medium
Average force exerted on a non-reflecting surface at normal incidence is 2.4×10−4N. If 360W/cm2 is the light energy flux during span of 1 hour 30 minutes, Then the area of the surface is:
Physicselectromagnetic-waves2024easy
Match List I with List II :
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LIST I
EM-Wave
LIST II
Wavelength Range
A.
Infra-red
I.
<10−3 nm
B.
Ultraviolet
II.
400 nm to 1 nm
C.
X-rays
III.
1 mm to 700 nm
D.
Gamma rays
IV.
1 nm to 10−3 nm
Choose the correct answer from the options given below :
Physicselectromagnetic-waves2024medium
In the given electromagnetic wave Ey=600sin(ωt−kx)Vm−1, intensity of the associated light beam is (in W/m2 : (Given ϵ0=9×10−12C2N−1m−2 )
Physicselectromagnetic-waves2024easy
Electromagnetic waves travel in a medium with speed of 1.5×108ms−1. The relative permeability of the medium is 2.0. The relative permittivity will be:
Physicswork-power-and-energy2024medium
A ball suspended by a thread swings in a vertical plane so that its magnitude of acceleration in the extreme position and lowest position are equal. The angle (θ) of thread deflection in the extreme position will be :
Physicswork-power-and-energy2024medium
A bullet is fired into a fixed target looses one third of its velocity after travelling 4cm. It penetrates further D×10−3m before coming to rest. The value of D is :
Physicswork-power-and-energy2024medium
A body of mass 2kg begins to move under the action of a time dependent force given by F=(6ti^+6t2j^)N. The power developed by the force at the time t is given by:
Physicswork-power-and-energy2024easy
A block of mass 100kg slides over a distance of 10m on a horizontal surface. If the co-efficient of friction between the surfaces is 0.4, then the work done against friction (inJ) is :
Physicswork-power-and-energy2024easy
The potential energy function (in J ) of a particle in a region of space is given as U=(2x2+3y3+2z). Here x,y and z are in meter. The magnitude of x-component of force (in N ) acting on the particle at point P(1,2,3)m is :
Physicswork-power-and-energy2024easy
A bob of mass 'm' is suspended by a light string of length 'L'. It is imparted a minimum horizontal velocity at the lowest point A such that it just completes half circle reaching the top most position B. The ratio of kinetic energies (K.E)B(K.E)A is :
Physicswork-power-and-energy2024easy
A block of mass 1kg is pushed up a surface inclined to horizontal at an angle of 60∘ by a force of 10N parallel to the inclined surface as shown in figure. When the block is pushed up by 10m along inclined surface, the work done against frictional force is :
[g=10m/s2]
Physicswork-power-and-energy2024easy
A particle is placed at the point A of a frictionless track ABC as shown in figure. It is gently pushed towards right. The speed of the particle when it reaches the point B is :
(Take g=10m/s2).
Physicswork-power-and-energy2024easy
A particle of mass m moves on a straight line with its velocity increasing with distance according to the equation v=αx, where α is a constant. The total work done by all the forces applied on the particle during its displacement from x=0 to x=d, will be :
Physicswork-power-and-energy2024easy
If a rubber ball falls from a height h and rebounds upto the height of h/2. The percentage loss of total energy of the initial system as well as velocity ball before it strikes the ground, respectively, are :
Physicswork-power-and-energy2024medium
A body of mkg slides from rest along the curve of vertical circle from point A to B in friction less path. The velocity of the body at B is:
(given, R=14m,g=10m/s2 and 2=1.4)
Physicswork-power-and-energy2024medium
A block is simply released from the top of an inclined plane as shown in the figure above. The maximum compression in the spring when the block hits the spring is :