Una rueda gira 160 veces en 20[s]. Calcule su periodo (s) y frecuencia (Hz)

The speed of light in a material is 0.50 c. what is the critical angle of a light ray at the interface between the material and a vacuum?

An object has a weight of 500 on earth what is the mass of this object

Refrigerant-134a flows through a carnot heat pump cycle at 0.5 kg/s. it is known that the maximum absolute temperature in the cycle is 1.1 times the minimum absolute temperature, and the net power input to the cycle is 2.5 kw. if the refrigerant changes from a saturated vapor to a saturated liquid during the heat rejection process, determine the maximum magnitude of the enthalpy of vaporization for this process in kj/kg (with 3 significant figures).