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The dimensional formula for Planck's con...

The dimensional formula for Planck's constant and gravitational constant G respectively are :-

A

`[ML^(3)T^(-2)], [M^(-1)L^(2)T^(-3)]`

B

`[ML^(2)T^(-1)], [M^(-1)L^(3)T^(-2)]`

C

`[ML^(3)T^(-2)], [M^(-1)L^(2)T^(2)]`

D

`[MLT^(-3)], [M^(-1)L^(3)T^(-3)]`

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To find the dimensional formulas for Planck's constant (h) and the gravitational constant (G), we can follow these steps: ### Step 1: Dimensional Formula for Planck's Constant (h) 1. **Understanding the relationship**: Planck's constant is defined through the equation \( E = h \nu \), where: - \( E \) is the energy of a photon. - \( \nu \) (nu) is the frequency of radiation. 2. **Rearranging the equation**: We can express Planck's constant as: \[ h = \frac{E}{\nu} \] 3. **Finding the dimensions of energy (E)**: The dimensional formula for energy is: \[ [E] = [\text{mass}] \times [\text{length}]^2 \times [\text{time}]^{-2} = M^1 L^2 T^{-2} \] 4. **Finding the dimensions of frequency (\( \nu \))**: Frequency is the reciprocal of time: \[ [\nu] = T^{-1} \] 5. **Substituting the dimensions into the formula for h**: \[ [h] = \frac{[E]}{[\nu]} = \frac{M^1 L^2 T^{-2}}{T^{-1}} = M^1 L^2 T^{-1} \] ### Step 2: Dimensional Formula for Gravitational Constant (G) 1. **Understanding the relationship**: The gravitational force \( F \) between two masses \( M \) and \( m \) separated by a distance \( r \) is given by: \[ F = \frac{G M m}{r^2} \] 2. **Rearranging the equation**: We can express \( G \) as: \[ G = \frac{F r^2}{M m} \] 3. **Finding the dimensions of force (F)**: The dimensional formula for force is: \[ [F] = [\text{mass}] \times [\text{length}] \times [\text{time}]^{-2} = M^1 L^1 T^{-2} \] 4. **Finding the dimensions of \( r^2 \)**: The dimensional formula for distance squared is: \[ [r^2] = [\text{length}]^2 = L^2 \] 5. **Finding the dimensions of mass (M and m)**: The dimensional formula for mass is: \[ [M] = M^1 \quad \text{and} \quad [m] = M^1 \] 6. **Substituting the dimensions into the formula for G**: \[ [G] = \frac{[F] [r^2]}{[M][m]} = \frac{(M^1 L^1 T^{-2})(L^2)}{(M^1)(M^1)} = \frac{M^1 L^3 T^{-2}}{M^2} = M^{-1} L^3 T^{-2} \] ### Final Result - The dimensional formula for Planck's constant \( h \) is: \[ [h] = M^1 L^2 T^{-1} \] - The dimensional formula for the gravitational constant \( G \) is: \[ [G] = M^{-1} L^3 T^{-2} \]

To find the dimensional formulas for Planck's constant (h) and the gravitational constant (G), we can follow these steps: ### Step 1: Dimensional Formula for Planck's Constant (h) 1. **Understanding the relationship**: Planck's constant is defined through the equation \( E = h \nu \), where: - \( E \) is the energy of a photon. - \( \nu \) (nu) is the frequency of radiation. ...
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