12th Standard Physics English Medium Free Online Test Creative One Mark questions with Answer Key - Part Four

12th Standard

Reg.No. :
•
•
•
•
•
•

Physics

Time : 00:10:00 Hrs
Total Marks : 10
10 x 1 = 10
1. The magnitude of torque on dipole is maximum if

(a)

θ=0o

(b)

θ=90o

(c)

θ=180o

(d)

θ=180o

2. The expression for water equivalent is

(a)

W=H(θ21)

(b)

W=$\frac { { \theta }_{ 2 }-{ \theta }_{ 1 } }{ H }$

(c)

both (a) and (b)

(d)

W=$\frac { H }{ { \theta }_{ 2 }-{ \theta }_{ 1 } }$

3. For an ideal transformer __________

(a)

EpIp = EsIs

(b)

EpEs = Ip

(c)

EpEs = Is

(d)

IpIs = EsIs

4. Accelerated charges would produce

(a)

sound waves

(b)

૪-rays

(c)

magnetic waves

(d)

electromagnetic waves

5. _________ spectra are used for making dyes

(a)

continuous emission

(b)

band emission

(c)

band absorption

(d)

line spectra

6. It is desired to photograph the image of an object placed at a distance of 3m from the plane mirror. The camera which is at a distance of 4.5 m from the mirror should be focused for a distance of

(a)

3 m

(b)

4.5 m

(c)

6 m

(d)

7.5 m

7. A small piece of wire bent into an L shape with upright and horizontal portion of equal length, is placed with the horizontal portion along the axis of concave mirror whose radius of curvature is 10 cm. If the bend is 20 cm from the pole of mirror, then the ratio of lengths of the image of upright and horizontal position of the wire is

(a)

1: 2

(b)

3: 1

(c)

1: 3

(d)

2: 1

8. Which phenomenon supports that matter has a wave nature?

(a)

electron momentum

(b)

electron diffraction

(c)

photon momentum

(d)

photon diffraction

9. The fig. represents the observed intensity of X-rays emitted by an X-ray tube as a function of wavelength. The sharp peaks A and B denote

(a)

continuous spectrum

(b)

band spectrum

(c)

characteristic spectrum

(d)

10. In a N-P-N transistor circuit, the emitter, collector and base current are respectively IE, IC and lB. The relation between them is

(a)

ICEB

(b)

IBCE

(c)

IB>IC>IE

(d)

IB>IC>IE