Assertion: Heat from the sun reaches the earth by convection.
Reason: Air can be heated only by convection.
Assertion: A wire carrying an electric current has no electric field around it.
Reason: Rate of flow of electron’s in one direction is equal to the rate of flow of protons in opposite direction.
Assertion: If an electron and proton enter a perpendicular magnetic field with equal momentum, then radius of curve for electron is more than that of proton.
Reason: Electron has less mass than proton.
Assertion: The ratio is more for helium gas than for hydrogen gas.
Reason: Atomic mass of helium is more than that of hydrogen.
Assertion: Our ears cannot distinguish two notes, one produced by a violin and other by a guitar, if they have exactly same intensity and same frequency.
Reason: When a musical instrument is played, it produces a fundamental note which is accompanied by a number of overtones called harmonics.
Assertion: The de-Broglie wavelength equation has significance for any microscope and submicroscopic particles.
Reason: de-Broglie wavelength is inversely proportional to the mass of the object its velocity is constant.
Assertion: In stationary wave, there is no transfer of energy.
Reason: The ratio of kinetic energy to potential energy is independent of the position.
Assertion: Electrons move from a region of higher potential to a region of lower potential.
Reason: An electron has less potential energy at a point where potential is higher and vice-versa.
Given below are two statements:
Assertion (A): | In a radioactive disintegration, an electron is emitted by the nucleus. |
Reason (R): | Electrons are present inside the nucleus. |
1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | (A) is false but (R) is true. |