Simple Harmonic Motion — Physics STD 12 Science — Question

The line that draws power supply to your house from street has:

The AC voltage across a resistance can be measured using a:

At the time of total solar eclipse, the spectrum of solar radiation would be

(a) A large number of dark Fraunhofer lines

(b) A less number of dark Fraunhofer lines

(c) No lines at all

(d) All Fraunhofer lines changed into brilliant colours

For uranium nucleus how does its mass vary with volume

(a) m ∝  V

(b) m ∝  1/V

(c) m ∝

(d) m ∝

A current of 10A is passing through a long wire which has semicircular loop of the radius 20cm as shown in the figure. Magnetic field produced at the centre of the loop is

(a) 10 πμT

(b) 5 πμT

(c) 4 πμT

(d) 2 πμT

The distinction between conductors, insulators and semiconductors is largely concerned with:

The ratio of the wavelengths for 2 → 1 transition in Li⁺⁺, He⁺  and H is

(a) 1 : 2 : 3

(b) 1 : 4 : 9

(c) 4 : 9 : 36

(d) 3 : 2 : 1

When yellow light is incident on a surface, no electrons are emitted while green light can emit. If red light is incident on the surface, then

(a) No electrons are emitted

(b) Photons are emitted

(c) Electrons of higher energy are emitted

(d) Electrons of lower energy are emitted

A heating coil is labelled 100 W, 220 V. The coil is cut in half and the two pieces are joined in parallel to the same source. The energy now liberated per second is

(a) 200 J

(b) 400 J

(c) 25 J

(d) 50 J

Figure shows the magnetic field lines in a magnetic field. A, B. and C are three points in this field. At what point is the magnetic field strong ?