The Sun releases vast amounts of energy. Its power output is 4 . 0 × 10 26 W . Estimate how much its mass decreases each second because of this energy loss.

Given, Power ( P ) = 4 . 0 × 10 26 W ( J s - 1 ) We know that decrease in mass per second is given by, ∆ m = P c 2 ⇒ ∆ m = 4 . 0 × 10 26 ( 3 × 10 8 ) 2 ⇒ ∆ m = 4 . 0 × 10 26 9 × 10 16 ⇒ ∆ m ≈ 4 . 4 × 10 9 Kg

(a) The mass of an atom of Fe 26 56 is 55 . 934937 u . Calculate its mass in $\mathrm{kg}$.

Given, m a s s o f F 26 56 e = 55 . 934937 u Now, ∵ 1 u = 1 . 6605 × 10 - 27 Kg ∴ Mass of Fe 26 56 = 55 . 934937 × 1 . 6605 × 10 - 27 Kg ⇒ Mass of Fe 26 56 = 9 . 2880 × 10 - 26 Kg

(b) The mass of an atom of O 8 16 is 2 . 656015 × 10 - 26 kg . Calculate its mass in $\mathrm{u}$.

Given, m a s s o f O 8 16 = 2 . 656015 × 10 - 26 kg Now, ∵ 1 u = 1 . 6605 × 10 - 27 Kg ∴ Mass of O 8 16 = 2 . 656015 × 10 - 26 1 . 6605 × 10 - 27 ⇒ Mass of O 8 16 = 15 . 995 u

Table gives the masses (in u) of several particles. Avogadro constant N A = 6 . 02 × 10 23 mol - 1 . Use the table to determine to three significant figures: (a) the mass in $\mathrm{kg}$ of a helium- 4 nucleus.

Given, m a s s o f H 2 4 e = 4 . 002602 u Now, ∵ 1 u = 1 . 6605 × 10 - 27 Kg ∴ Mass of H 2 4 e = 4 . 002602 × 1 . 6605 × 10 - 27 Kg ⇒ Mass of H 2 4 e ≈ 6 . 65 × 10 - 27 Kg

Table gives the masses (in u) of several particles. Avogadro constant N A = 6 . 02 × 10 23 mol - 1 . Use the table to determine to three significant figures: (b) the mass in gram (g) of $1.0$ mole of uranium-235 nuclei.

One mole of any substance has same mass in grams as it has in amu ∴ m = 235 . 043930 g

E M B I B E

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 29 - Nuclear Physics>Questions>Q 2

EASY

AS and A Level

IMPORTANT

Earn 100

Copy and complete this equation for the $\beta^{-}$ decay of a nucleus of argon: ${}_{18}^{41}{Ar} \to K + ?$

Important Questions on Nuclear Physics

EASY

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 29 - Nuclear Physics>Questions>Q 3

The Sun releases vast amounts of energy. Its power output is

4.0 \times 10^{26} W

. Estimate how much its mass decreases each second because of this energy loss.

EASY

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 29 - Nuclear Physics>Questions>Q 4

(a) Calculate the energy released if a $_{2}^{4} He$ nucleus is formed from separate stationary protons and neutrons. The masses of the particles are given in Table.

Question Image

EASY

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 29 - Nuclear Physics>Questions>Q 4

(b) Calculate also the energy released per nucleon.

Question Image

EASY

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 29 - Nuclear Physics>Questions>Q 5

The rest mass of a golf ball is $150 g$ .

Calculate its increase in mass when it is travelling at $50 {ms}^{- 1}$ . What is this as a percentage of its rest mass?

EASY

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 29 - Nuclear Physics>Questions>Q 6

(a) The mass of an atom of

{}_{26}^{56}{Fe}

is

55.934937 u

. Calculate its mass in $\mathrm{kg}$.

EASY

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 29 - Nuclear Physics>Questions>Q 6

(b) The mass of an atom of

{}_{8}^{16}O

is

2.656015 \times 10^{- 26} kg

. Calculate its mass in $\mathrm{u}$.

EASY

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 29 - Nuclear Physics>Questions>Q 7

Table gives the masses (in u) of several particles. $(Avogadro constant N_{A} = 6.02 \times 10^{23} {mol}^{- 1})$ . Use the table to determine to three significant figures:

Question Image

(a) the mass in $\mathrm{kg}$ of a helium- 4 nucleus.

EASY

AS and A Level

IMPORTANT

Physics for Cambridge International AS & A Level Coursebook 3rd Edition Digital Access>Chapter 29 - Nuclear Physics>Questions>Q 7

Table gives the masses (in u) of several particles. $(Avogadro constant N_{A} = 6.02 \times 10^{23} {mol}^{- 1})$ . Use the table to determine to three significant figures: