Dual Nature of Radiation and Matter — Physics STD 12 Science — Question

A particle is acted upon by a force of constant magnitude which is always perpendicular to the velocity of the particle. The motion of the particle takes place in a plane. It follows that:

1. Its velocity is constant.
2. Its acceleration is constant.
3. Its kinetic energy is constant.
4. It moves in a circular path.

Holes charge carries :

A wire carrying current i is shaped as shown. Section AB is a quarter circle of radius r.  The magnetic field is directed

(a) At an angle π/4  to the plane of the paper

(b) Perpendicular to the plane of the paper and directed in to the paper

(c) Along the bisector of the angle ACB  towards AB

(d) Along the bisector of the angle ACB away from AB

Photons absorbed in matter are converted to heat. A source emitting n photon/sec of frequency ν is used to convert 1kg of ice at 0°C to water at 0°C. Then, the time T taken for the conversion:

Comment on the statement given below:
In self-inductionWhen the current in a coil is increasing, induced emf opposes it
When the current in a coil is decreasing, induced emf supports it

The binding energy of nucleus is a measure of its

(a) Charge

(b) Mass

(c) Momentum

(d) Stability

Work function of lithium and copper are respectively 2.3 eV and 4.0 eV. Which one of the metal will be useful for the photoelectric cell working with visible light ? (h = 6.6 × 10^–34 J-s, c = 3 × 10⁸ m/s)

(a) Lithium

(b) Copper

(c) Both

(d) None of these

Find the false statement.

The maximum number of possible interference maxima for slit-separation equal to twice the wavelength in Young’s double-slit experiment is

(a) Infinite

(b) Five

(c) Three

(d) Zero