Volume of a Riemannian manifold with a scaled metric

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I'm confused with the volume of an n-dimensional Riemannian manifold with a scaled metric. Specifically, let $M$ be a Riemannian manifold with Riemannian metric $g$ and its volume denoted by $vol_g(M)$. If we endow $M$ with another metric

$$\widetilde{g}=\lambda g,\qquad \text{here $\lambda$ is a positive smooth function on $M$}$$

then, how about the volume $vol_{\widetilde{g}}(M)$ of with respect to $\widetilde{g}$? I know that the volume form

$$dv_{g}=\sqrt{\det\ g}\ dx^1\wedge\cdots \wedge dx^n .$$

So I guess that

$$dv_{\widetilde{g}}=\lambda^{n/2}dv_{g}, $$

and therefore

$$vol_{\widetilde{g}}(M)=\lambda^{n/2}vol_g(M) .$$

Do you think it is right? If not, how do we to calculate the volume $vol_{\widetilde{g}}(M)$ and figure out the relationship with $vol_g(M)$?

Thanks in advance!