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

The material of wire of potentiometer is

(a) Copper

(b) Steel

(c) Manganin

(d) Aluminium

The component of a vector is:

1. Always less than its magnitude.
2. Always greater than its magnitude.
3. Always equal to its magnitude.
4. None of these.

Beta particle An unknown particle is being studied in a magnetic field of variable intensity and direction. When the magnetic field is turned off, the particle is observed to move toward the earth. When the magnetic field is turned on, the particle is observed to continue to move toward the earth, no matter the strength or the direction of the magnetic field. Which of the particles listed below is most likely the unknown particle?

A conducting circular loop of radius r carries a constant current i. It is placed in a uniform magnetic field , such that   is perpendicular to the plane of the loop. The magnetic force acting on the loop is

(a) ir

(b) 2πri

(c) Zero

(d) πri

If the capacitors having capacitance C₁ and C₂ are connected in series then their resultant capacitance is given by:

The difference between the mass of a nucleus and the combined mass of its nucleons is:

A narrow electron beam passes undeviated through an electric field E = 3  and an overlapping magnetic field B = 2 . If electric field and magnetic field are mutually perpendicular. The speed of the electrons is

(a) 60 m/s

(b) 10.3

(c) 1.5

(d) 0.67

Which of the following particles will experience maximum magnetic force circle when projected with the same velocity perpendicular to a magnetic field?

The relation between I_p and V_p for a triode is   , Keeping the grid potential constant at 1V, the value of r_p will be

(a) 8 kW

(b) 4 kW

(c) 2 kW

(d) 8 kW

The work function of a metal is 1.6  J. When the metal surface is illuminated by the light of wavelength  6400 Å, then the maximum kinetic energy of emitted photo-electrons will be (Planck's constant h = 6.4 )

(a) 14

(b) 2.8

(c) 1.4

(d) 1.4