1
JEE Main 2022 (Online) 25th July Evening Shift
+4
-1

The ratio of wavelengths of proton and deuteron accelerated by potential Vp and Vd is 1 : $$\sqrt2$$. Then the ratio of Vp to Vd will be :

A
1 : 1
B
$$\sqrt2$$ : 1
C
2 : 1
D
4 : 1
2
JEE Main 2022 (Online) 25th July Evening Shift
+4
-1

Hydrogen atom from excited state comes to the ground state by emitting a photon of wavelength $$\lambda$$. The value of principal quantum number '$$n$$' of the excited state will be : ($$\mathrm{R}:$$ Rydberg constant)

A
$$\sqrt{\frac{\lambda \mathrm{R}}{\lambda-1}}$$
B
$$\sqrt{\frac{\lambda \mathrm{R}}{\lambda \mathrm{R}-1}}$$
C
$$\sqrt{\frac{\lambda}{\lambda \mathrm{R}-1}}$$
D
$$\sqrt{\frac{\lambda R^{2}}{\lambda R-1}}$$
3
JEE Main 2022 (Online) 25th July Morning Shift
+4
-1

The momentum of an electron revolving in $$\mathrm{n}^{\text {th }}$$ orbit is given by :

(Symbols have their usual meanings)

A
$$\frac{\mathrm{nh}}{2 \pi \mathrm{r}}$$
B
$$\frac{n h}{2 r}$$
C
$$\frac{\mathrm{nh}}{2 \pi}$$
D
$$\frac{2 \pi r}{\mathrm{nh}}$$
4
JEE Main 2022 (Online) 30th June Morning Shift
+4
-1

A cyclotron is working at a frequency of 10 MHz. If the radius of its dees is 60 cm. The maximum kinetic energy of accelerated proton will be :

(Take : e = 1.6 $$\times$$ 10$$-$$19 C, mp = 1.67 $$\times$$ 10$$-$$27 kg)

A
7.4 MeV
B
14.86 MeV
C
7.4 GeV
D
704 GeV
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