4.90 SAE 10W oil at 20°C flows through a straight horizontal pipe. The pressure gradient is a con...

4.90 SAE 10W oil at 20°C flows through a straight horizontal pipe. The pressure gradient is a constant 400 Pa/m. (a) What is the appropriate pipe diameter Din cm if the Reynolds number Rep of the flow is to be exactly 1000? (b) For case a, what is the flow rate in m/h? For SAE 10W oil, from Appendix A.3, p= 870 kg/m' and p = 0.104 kg/(ms).