A barometer kept in an elevator reads $76cm$ when it is at rest. What will be barometric reading when the elevator accelerates upwards?

The correct option is A $\frac{(g+a)h_0}{g}$

When a body moves upward the acceleration due to gravity is,

$g^{\prime }=g+a$

Hence, the pressure is

$P=h_0\rho \left(g+a\right)$

$=\frac{h_0\left(g+a\right)}{g}$

Hence, the barometer reading will be more than the measured value at rest.