1
NEET 2018
MCQ (Single Correct Answer)
+4
-1
Change Language
When the light of frequency 2$${\upsilon _0}$$ (where $${\upsilon _0}$$ is threshold frequency), is incident on a metal plate, the maximum velocity of electrons emitted is v1 . When the frequency of the incident radiation is increased to 5$${\upsilon _0}$$ , the maximum velocity of electrons emitted from the same plate is v2 . The ratio of v1 to v2 is
A
1 : 2
B
1 : 4
C
4 : 1
D
2 : 1
2
NEET 2018
MCQ (Single Correct Answer)
+4
-1
Change Language
An object is placed at a distance of 40 cm from a concave mirror of focal length 15 cm. If the object is displaced through a distance of 20 cm towards the mirror, the displacement of the image will be
A
30 cm away from the mirror
B
36 cm away from the mirror
C
30 cm towards the mirror
D
36 cm towards the mirror
3
NEET 2018
MCQ (Single Correct Answer)
+4
-1
Change Language
In a p-n junction diode, change in temperature due to heating
A
affects only reverse resistance
B
affects only forward resistance
C
does not affect resistance of p-n junction
D
affects the overall V - I characteristics of p-n junction
4
NEET 2018
MCQ (Single Correct Answer)
+4
-1
Change Language
A block of mass m is placed on a smooth inclined wedge ABC of inclination q as shown in the figure. The wedge is given an acceleration ‘a’ towards the right. The relation between a and q for the block to remain stationary on the wedge is NEET 2018 Physics - Laws of Motion Question 14 English
A
$$a = {g \over {\cos ec\theta }}$$
B
$$a = {g \over {\cos ec\theta }}$$
C
$$a = g\cos \theta $$
D
$$a = g\tan \theta $$