Mass Energy Equivalence

Q. If mass energy equivalence is taken into account, when water is cooled to form ice, the mass of water should

1. First increase then decrease
2. Increase
3. Remain unchanged
4. Decrease

Q. Consider the decay of a free neutron at rest : n →p + e– Show that the two-body decay of this type must necessarily give an electron of fixed energy and, therefore, cannot account for the observed continuous energy distribution in the b-decay of a neutron or a nucleus (Fig. 6.19). [Note: The simple result of this exercise was one among the several arguments advanced by W. Pauli to predict the existence of a third particle in the decay products of βdecay. This particle is known as neutrino. We now know that it is a particle of intrinsic spin ½ (like e—, p or n), but is neutral, and either massless or having an extremely small mass (compared to the mass of electron) and which interacts very weakly with matter. The correct decay process of neutron is : n → p + e – + υ ]

Q. Mass can be converted into energy.

1. False
2. True

Q. In hydrogen spectrum, the ratio of the longest wavelength in the Lyman series to the longest wavelength in the Balmer series is -

1. $\frac{27}{5}$
2. $\frac{5}{9}$
3. $\frac{5}{3}$
4. $\frac{5}{27}$

Q. 24The ppt. Of caf2 ksp 1.7×10power- is obtained 2hwn equal volume r mixed 1 10power-3mM ca, 10power-5 f

Q. atomic structure is stable due to which force whereas nuclea structure is stable due to which force ??

Q. The industrial revolution in England and Western Europe more than two centuries ago was triggered by some key scientific and technological advances. What were these advances?

Q. If we completely annihilate a hair of your body that has a mass of $1\mathrm{\mu g}$, how much energy will we get in the process?

1. $9\times {10}^7\text{J}$
2. $8\times {10}^7\text{J}$
3. $9\times {10}^{10}\text{J}$
4. $8\times {10}^{10}\text{J}$

Q. The mass defect in a particular nuclear reaction is 0.3 grams. The amount of energy liberated in kilowatt hours is
(Velocity of light =$3\times {10}^8$m/s )

1. $1.5\times {10}^6$
   
2. $2.5\times {10}^6$
   
3. $3\times {10}^6$
   
4. $7.5\times {10}^6$

Q. Radioactivity occurs when the rest energy of the products is less than the rest energy of the reactants.

1. False
2. True

Q. what is energy mass equivalence?

Q.

Two particles interact by conservative forces and no other forces act. They complete a round trip ending at the points where they started. For this round-trip mark out the incorrect statement(s)

1. The total KE might have a different value at the beginning, and at the end.

2. The total PE might have a different value at the beginning, and at the end.

3. The total mechanical energy might have a different value at the beginning, and at the end.

4. The total mechanical energy might have a same value at the beginning, and at the end.

Q. Is mass a form of energy? Justify your answer?

Q. A man is suffering from Hypermetropia. He has normal far point. He uses an appropriate lens to correct his vision. In doing which of the following activities, use of glasses is not useful?

1. driving.
2. watching TV.
3. All of the above
4. playing cricket.

Q. If the enthalpies of formation of C3 h8 CO2 and H2O standard condition and - 104 kilo joule per mole - 394 kilo joule per mole and -2 86 kilo joule per mole respectively then the standard enthalpy of combustion of 66 gram of C3 h8 is

Q. Given are three different stages of an ancient and deadly two-body system: the bow and the arrow. If m represents the mass of the 'bow-arrow system', how can you compare the different cases?

1. $m_1=m_2=m_3$
2. $m_1$ < $m_2=m_3$
3. $m_1$ > $m_2=m_3$
4. $m_1$ < $m_2$ < $m_3.$