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To compare the velocity of a miniature sports car in 1:10 scale with a full-scale car, you can use the Reynolds number as a benchmark. The Reynolds number is a dimensionless quantity that describes the ratio of inertial forces to viscous forces in a fluid flow. It is defined as:

Re=fracrhovLmu

where rho is the density of the fluid, v is the velocity of the fluid, L is a characteristic length scale, and mu is the dynamic viscosity of the fluid.

To maintain the same Reynolds number between the miniature car and the full-scale car, you need to scale the velocity of the miniature car by the ratio of the characteristic length scales. In your case, the characteristic length scale of the miniature car is 1/10 of the full-scale car. Therefore, you need to scale the velocity of the miniature car by a factor of 10 to maintain the same Reynolds number.

Reference: https://www.usna.edu/NAOE/_files/documents/Faculty/schultz/uno onlineSchultz,%20Flack%20-%20Reynolds%20Number%20Scaling,%202013.pdf