JEE Main 2023 · 6 Apr 2023 Shift 1

By what percentage will the transmission range of a TV tower be affected when the height of the tower is increased by 21% ?

1. A14%
2. B10%
3. C12%
4. D15%

A small ball of mass M and density ρ is dropped in a viscous liquid of density ρ₀. After some time, the ball falls with a constant velocity. What is the viscous force on the ball ?

1. AF = Mg (1 − ρ₀/ρ)
2. BF = Mg (1 + ρ₀/ρ)
3. CF = Mg (1 + ρ/ρ₀)
4. DF = Mg (1 ± ρρ₀)

The kinetic energy of an electron, α-particle and a proton are given as 4 K, 2 K and K respectively. The de-Broglie wavelength associated with electron (λₑ), α-particle (λₐ) and the proton (λₚ) are as follows:

1. Aλₐ ≫ λₚ ≫ λₑ
2. Bλₐ < λₚ < λₑ
3. Cλₐ = λₚ < λₑ
4. Dλₐ = λₚ > λₑ

A monochromatic light wave with wavelength λ₁ and frequency ν₁ in air enters another medium. If the angle of incidence and angle of refraction at the interface are 45° and 30° respectively, then the wavelength λ₂ and frequency ν₂ of the refracted wave are:

1. Aλ₂ = √2λ₁, ν₂ = ν₁
2. Bλ₂ = 1/√2 λ₁, ν₂ = ν₁
3. Cλ₂ = λ₁, ν₂ = 1/√2 ν₁
4. Dλ₂ = λ₁, ν₂ = √2ν₁

For the plane electromagnetic wave given by E = E₀ sin (ωt − kx) and B = B₀ sin (ωt − kx), the ratio of average electric energy density to average magnetic energy density is

1. A1
2. B2
3. C4
4. D1/2

The induced emf can be produced in a coil by

1. Amoving the coil with uniform speed inside uniform magnetic field
2. Bmoving the coil with non uniform speed inside uniform magnetic field
3. Crotating the coil inside the uniform magnetic field
4. Dchanging the area of the coil inside the uniform magnetic field Choose the correct answer from the options given below:

A particle is moving with constant speed in a circular path. When the particle turns by an angle 90°, the ratio of instantaneous velocity to its average velocity is π : x√2. The value of x will be -

1. A7
2. B5
3. C2
4. D1

A long straight wire of circular cross-section (radius a) is carrying steady current I. The current I is uniformly distributed across this cross-section. The magnetic field is

1. Auniform in the region r < a and inversely proportional to distance r from the axis, in the region r > a
2. Bzero in the region r < a and inversely proportional to r in the region r > a
3. Cdirectly proportional to r in the region r < a and inversely proportional to r in the region r > a
4. Dinversely proportional to r in the region r < a and uniform throughout in the region r > a