1
JEE Main 2020 (Online) 4th September Morning Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
Choose the correct option relating wave lengths of different parts of electromagnetic wave spectrum:
A
$$\lambda $$radio waves > $$\lambda $$micro waves > $$\lambda $$visible > $$\lambda $$x-rays
B
$$\lambda $$visible > $$\lambda $$x-rays > $$\lambda $$radio waves > $$\lambda $$micro waves
C
$$\lambda $$visible < $$\lambda $$micro waves < $$\lambda $$radio waves < $$\lambda $$x-rays
D
$$\lambda $$x-rays < $$\lambda $$micro waves < $$\lambda $$radio waves < $$\lambda $$visible
2
JEE Main 2020 (Online) 4th September Morning Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
A air bubble of radius 1 cm in water has an upward acceleration 9.8 cm s–2. The density of water is 1 gm cm–3 and water offers negligible drag force on the bubble. The mass of the bubble is (g = 980 cm/s2).
A
1.52 gm
B
4.51 gm
C
3.15 gm
D
4.15 gm
3
JEE Main 2020 (Online) 4th September Morning Slot
Numerical
+4
-0
Change Language
A closed vessel contains 0.1 mole of a monoatomic ideal gas at 200 K. If 0.05 mole of the same gas at 400 K is added to it, the final equilibrium temperature (in K) of the gas in the vessel will be close to _______.
Your input ____
4
JEE Main 2020 (Online) 4th September Morning Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
Particle A of mass mA = $${m \over 2}$$ moving along the x-axis with velocity v0 collides elastically with another particle B at rest having mass mB = $${m \over 3}$$. If both particles move along the x-axis after the collision, the change $$\Delta $$$$\lambda $$ in de-Broglie wavlength of particle A, in terms of its de-Broglie wavelength ($$\lambda $$0) before collision is :
A
$$\Delta $$$$\lambda $$ = $${5 \over 2}{\lambda _0}$$
B
$$\Delta $$$$\lambda $$ = $${3 \over 2}{\lambda _0}$$
C
$$\Delta $$$$\lambda $$ = 2$$\lambda $$0
D
$$\Delta $$$$\lambda $$ = 4$$\lambda $$0

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