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1.For a body dropped from a height, h, the speed, V,with which it strikes the ground depends only on h
and g and a dimensionless numerical factor. Obtain an expression connecting v, h and g.
A 200-g block is pressed against a spring of force constant 1.40 kN/m until the block compresses the spring 10.0 cm. The spring rests at the bottom of a ramp inclined at 60.08 to the horizontal. Using energy considerations, determine how far up the incline the block moves from its initial position before it stops (a) if the ramp exerts no friction force on the block and (b) if the coefficient of kinetic friction is 0.400.
The supporting cables AB and AC are oriented so that the components of the 360-lb force along AB and AC are 185 lb and 200 lb, respectively. Determine the angles α and β
378 𝑙𝑝𝑠 of air is isothermally compressed at 27℃ and 1379 𝑘𝑃𝑎𝑎; 𝑝2 = 4136 𝑘𝑃𝑎𝑎. For both nonflow and steady-flow (𝑉1 = 23 𝑚 𝑠 , 𝑉2 = 46 𝑚 𝑠 , ∆𝑃 = 0) processes, compute (a) ∫ 𝑝𝑑𝑉 𝑎𝑛𝑑 − ∫ 𝑉𝑑𝑝 (b) ∆𝑈, ∆𝐻, 𝑎𝑛𝑑 ∆𝑆 (c) 𝑊 𝑎𝑛𝑑 𝑄
Assume that a 5-lb ideal gas with 𝑅 = 38.7 𝑓𝑡.𝑙𝑏 𝑙𝑏.°𝑅 and 𝑘 = 1.668 have 300 Btu of heat added during reversible constant pressure change of state. The initial temperature is 80℉. Determine (a) the final temperature; (b) the change of enthalpy, internal energy, and entropy; and (c) the work.
A nozzle is designed to expand air from 689 𝑘𝑃𝑎𝑎 and 32℃ to 138 𝑘𝑃𝑎𝑎. Assume an isentropic expansion and negligible approach velocity. The airflow rate is 1.36 kg/s. Calculate (a) the exit velocity; (b) the proper exit cross-sectional area.
Assume 2 𝑙𝑏 of gas, for which 𝑅 = 26 𝑓𝑡.𝑙𝑏 𝑙𝑏.°𝑅 and 𝑘 = 1.10, undergoing a polytropic process from 𝑝1 = 15 𝑝𝑠𝑖𝑎 and 𝑡1 = 100℉ to 𝑝2 = 75 𝑝𝑠𝑖𝑎 and 𝑉2 = 3.72 𝑓𝑡3 . For both nonflow and steady-flow (∆𝑃 = 0, ∆𝐾 = 0) processes, determine (a) 𝑛 in 𝑝𝑉 𝑛 = 𝐶; (b) ∆𝐻, ∆𝑈, 𝑎𝑛𝑑 ∆𝑆; (c) ∫ 𝑝𝑑𝑉 𝑎𝑛𝑑 − ∫ 𝑉𝑑𝑝; (d) 𝑊 𝑎𝑛𝑑 𝑄.
