
- A160 V
- B$80\sqrt{80}$
- C80 V
- Dzero

Explanation:
VZY = VC - VL = 0
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
For substances hysteresis (B - H) curves are given as shown in figure. For making temporary magnet which of the following is best.
|
(a)
|
(b)
|
(c)
|
(d)
|
The direction of magnetic lines of forces close to a straight conductor carrying current will be
|
(a) Along the length of the conductor |
|
(a) Along the length of the conductor |
|
(c) Circular in a plane perpendicular to the conductor |
|
(d) Helical |
A combination of two thin lenses with focal lengths and
respectively forms an image of distant object at distance 60 cm when lenses are in contact. The position of this image shifts by 30 cm towards the combination when two lenses are separated by 10 cm. The corresponding values of
and
are
|
(a) 30 cm,-60 cm |
(b) 20 cm, -30 cm |
(c) 15 cm, -20 cm |
(d) 12 cm, - 15 cm |
The wavelength of
X-rays produced by an X-ray tube is 0.76 Å. The atomic number of the anode material of the tube is
| (a) 20 | (b) 60 | (c) 40 | (d) 80 |
Under which of the following conditions will a convex mirror of focal length f produce an image that is erect, diminished and virtual
|
(a) Only when 2f > u > f |
(b) Only when u = f |
|
(c) Only when u < f |
(d) Always |
In a working nuclear reactor, Cadmium rods, (control rods) are used to
|
(a) Speed up neutrons |
(b) Slow down neutrons |
|
(c) Absorb some neutrons |
(d) Absorb all neutrons |
The only property possessed by ferromagnetic substance is
|
(a) Hysteresis |
(b) Susceptibility |
|
(c) Directional property |
(d) Attracting magnetic substances |
A luminous object is placed at a distance of 30 cm from the convex lens of focal length 20 cm. On the other side of the lens, at what distance from the lens a convex mirror of radius of curvature 10 cm be placed in order to have an upright image of the object coincident with it
| (a) 12 cm | (b) 30 cm |
(c) 50 cm |
(d) 60 cm |
Three bulbs of 40 W, 60 W, 100 W are arranged in series with 220 volt supply which bulb has minimum resistance
|
(a) 100 W |
(b) 40 W |
(c) 60 W |
(d) Equal in all bulbs |