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The primary X-ray emission in active galactic nuclei (AGN) originates in acompact region called the corona located very close to the super-massive blackhole and the accretion disk. The knowledge of the cut-off energy ($E_{cut}$) ofthe primary X-ray continuum in an AGN is very important as it carriesinformation on the physical characteristics of the hot X-ray emitting corona.We present here the results of our investigation on the spectral properties ofa sample of 10 nearby AGN (0.005 $<$ $z$ $<$ 0.037) observed with the {\itNuclear Spectroscopic Telescope Array (NuSTAR)} . From fitting of the {\itNuSTAR} data of 10 sources, we derived clear $E_{cut}$ values for the firsttime in 8 sources and a lower limit in one source, thereby, doubling the numberof AGN with $E_{cut}$ measurements from {\it NuSTAR} data. Broad Fe K$\alpha$line was noticed in 7 sources, while, excess emission in the energy rangebeyond $\sim$15 keV arising from Compton reflection was seen in all thesources. We also investigated the correlation of $E_{cut}$ with variousphysical characteristics of the AGN such as black hole mass ($M_{BH}$),Eddington ratio ($\lambda_{Edd.}$) and X-ray photon index ($\Gamma$). We foundno correlation between $E_{cut}$ and $M_{BH}$ and between $E_{cut}$ and$\lambda_{Edd.}$, however, $E_{cut}$ correlates with $\Gamma$ in a complexmanner. Also, timing analysis of the 10 sources indicates that they all arevariable with indications of more variations in the soft band relative to thehard band in some individual sources, however, considering all the sourcestogether, the variations are indistinguishable between hard and soft bands.

Study of X-ray variability and coronae of Seyfert galaxies using NuSTAR