potential energy = m^x g^y h^z find value of x y z . m =mass of particle . g = gravitational acceleration . h= height of particle
Answers
Dear student,
It is given that potential energy = m^x g^y h^z. And we also know by formula that potential energy = mgh ( for gravitational potential ).
We need to find the values of x, y and z.
Method 1
Since, mass = m
= M¹ ____(1)
acceleration due to gravity = g
= LT⁻² ____(2)
height = h
= L¹ _____(3)
From (1), (2) and (3) and equating with m^x g^y h^z, we obtain;
m^x g^y h^z = M¹L¹T⁻² × L¹
m^x g^y h^z = M¹L²T⁻²
x, y, z = 1, 2, - 2
Hence, the values of x, y and z are 1, 2 and - 2 respectively.
Method 2
We know that any form of energy has a fixed dimension. And we know by dimensional analysis that the dimensions of energy are M¹L²T⁻².
Equating m^x g^y h^z with the dimensions of energy, we get;
m^x g^y h^z = M¹L¹T⁻² × L¹
m^x g^y h^z = M¹L²T⁻²
x, y, z = 1, 2, - 2
Therefore, the x = 1, y = 2 and z = - 2.
Given :
E = G phqcr
∴ [ML 2T−2]=[M−1L3T−2]p× [ML 2T−1]q ×[M0LT−1]r
⟹ [ML 2T−2] =[M(−p+q)L(3p+2q+r)T(−2p−q−r)]
Equating both sides, we get:
−p+q=1 . . . . . . . .(1)
3p+2q+r=2 . . . . . . . . (2)
−2p−q−r=−2 . . . . . . . . . .(3)
Adding (2) and (3), we get: p+q=0 . . . . (4)
Solving (1) and (4),
⟹p=−21 and q=21
Now from (2),
3×(−21)+2×21+r=2
⟹r=25