Let \(L_1\) and \(L_2\) be the orbital angular momentum of an electron in the first and second excited states of the hydrogen atom, respectively. According to Bohr's model, the ratio \(L_1:L_2\) is:
1. \(1:2\)
2. \(2:1\)
3. \(3:2\)
4. \(2:3\)
The output of the logic circuit shown is equivalent to a/an:
1. \(\text{OR}\) gate
2. \(\text{NOR}\) gate
3. \(\text{AND}\) gate
4. \(\text{NAND}\) gate
1. | a parabolic path |
2. | the original path |
3. | a helical path |
4. | a circular path |
A string is wrapped along the rim of a wheel of moment of inertia \(0.10\) kg-m2 and radius \(10\) cm. If the string is now pulled by a force of \(10\) N, then the wheel starts to rotate about its axis from rest. The angular velocity of the wheel after \(2\) s will be:
1. | \(40\) rad/s | 2. | \(80\) rad/s |
3. | \(10\) rad/s | 4. | \(20\) rad/s |
A stone is thrown vertically downwards with an initial velocity of \(40\) m/s from the top of a building. If it reaches the ground with a velocity of \(60\) m/s, then the height of the building is: (Take \(g=10\) m/s2)
1. | \(120\) m | 2. | \(140\) m |
3. | \(80\) m | 4. | \(100\) m |
Rain is falling vertically downward with a speed of \(35~\text{m/s}\). Wind starts blowing after some time with a speed of \(12~\text{m/s}\) in East to West direction. The direction in which a boy standing at the place should hold his umbrella is:
1. | \(\text{tan}^{-1}\Big(\dfrac{12}{37}\Big)\) with respect to rain |
2. | \(\text{tan}^{-1}\Big(\dfrac{12}{37}\Big)\) with respect to wind |
3. | \(\text{tan}^{-1}\Big(\dfrac{12}{35}\Big)\) with respect to rain |
4. | \(\text{tan}^{-1}\Big(\dfrac{12}{35}\Big)\) with respect to wind |
1. | \(10\hat i~\text{nT}\) | 2. | \(-10\hat i~\text{nT}\) |
3. | \(\hat i~\text{nT}\) | 4. | \(-\hat i~\text{nT}\) |
In a photoelectric experiment, blue light is capable of ejecting a photoelectron from a specific metal while green light is not able to eject a photoelectron. Ejection of photoelectrons is also possible using light of the colour:
1. yellow
2. red
3. violet
4. orange
A string of length \(l\) is fixed at both ends and is vibrating in second harmonic. The amplitude at antinode is \(2\) mm. The amplitude of a particle at a distance \(l/8\) from the fixed end is:
1. \(2\sqrt2~\text{mm}\)
2. \(4~\text{mm}\)
3. \(\sqrt2~\text{mm}\)
4. \(2\sqrt3~\text{mm}\)