31.

The magnetic force acting on a charged particle of charge -2 μC in a magnetic field of 2T acting in y direction, when the particle velocity is 

• 8N in -z direction

• 4N in z direction

• 8 N in y direction

• 8 N in y direction

See the electrical circuit shown in this figure. Which of the following equations is a correct equation for it?

The two ends f a rod of length L and a uniform cross -sectional area A are kept at two temperatures T₁ and T₂ (T₂ > T₁) .The rate of heat transfer, dQ/dt, through the rod in steady state is given by

A galvanometer having a coil resistance of 60 Ω shows full-scale deflection when a current of 1.0 A passes through it. It can be converted into an ammeter to read currents up to 5.0 A by

• putting in parallel a resistance of 240 Ω

• putting in series a resistance of 15 Ω

• putting in series a resistance of 240 Ω

• putting in series a resistance of 240 Ω

The electric potential at a point (x, y, Z) is given by

V = - x²y -xz³ + 4

The electric field E at that point is

Power dissipated in an L-C-R series circuit connected to an AC source of emf is

In the nuclear decay given below,


the particle emitted in the sequence are

• β, α, γ

• γ, β, α, 

•  β,γ, α

•  β,γ, α

A p-n photodiode is fabricated from a semiconductor with a band gap of 2.5 eV. It ca detect a signal of wavelength

• 6000 A^o

• 4000 nm

• 6000 nm

• 6000 nm

If a diamagnetic substance is brought near the north or the south pole of a bar magnet, it is 

• repelled by both the poles

• repelled by the north pole and attracted by the south pole

• attracted by the north pole and repelled by the south  pole

• attracted by the north pole and repelled by the south  pole

The number of beta particles emitted by radioactive substance is twice the number  of alpha particle emitted by it. The resulting daughter is an 

• isobar of parent

• isomer of parent

• isotone of parent

• isotone of parent