Question

User Guide YS1121 Benito Joseph 1.00 Question: A bullet is shot horizontally with a speed of 438 m/s at a height of 1,40 m above a person's ears. The temperature of the air is 39.1 'C. You can assume that the speed of sound inaris 331 m/s when the air is O'C. Part 1) What is the speed of sound in air in this case? V= m/s Part 2) What is the Mach number of this bullet? Mach number = Part 3) What horizontal distance will the bullet have travelled from them when the person hears the shock wave? Check Next page ty Privacy Content & Social Media Disclaimer as Benito Joseph (Logout Copyright & Disclaimer Accessibility Site Map students experiencing difficulties using Moodle? Contact External TELT Support for assistance supporunsw.edu.au 2 9365 3331 Tuesday 17 September 2019 rovider Code DOONBG. ABN 57 195873 179 Sydney, NSW 2052, Australia

Answer 1

given problem can be solved by using below formula

V$_{o}$=V$_{t}$(1-$_\frac{t}{546}$)

mach number=velocity of object/velocity of sound

horizontal distance=horizontal velocity*time

Given, = 1.40 norisontel speed = 438 mis . Height, h= 1.40m . Temperature of air, t = 39.10 speed of sound in air at oc; v = 331 ml - Test 1 1 speed of sound in air at 39.1c is Calculete as follown v = v(- 6) 0 Where vo= speed of sound at oc į = speed of sound at the t = temperature substilute vo= 331 mls, - t = 39.1c inequation Vo = vt (146) 331 = V+ (-es 331 = V (1-0.072) 331 10.93) 331 = 356 mis. 0.93 speed of sound in air at 39.16 V = 356 mis

part 2 : - Mach number of the sullet is celulete by the following formula. Mach number = speed of the object - speed of sound | speed of bellet = 435 mis speed of sound y = 356 m/s sulstilete these valus in en @ we get Mach number = 438 7 st 356 = 1.2 Mach number of bulkt, M = 1:21 V=43&ull Pet 3: -1 اش Ve436 mis h. 1.401 y-anis : y = 4 + Voy! +Qyt? Os 1-10 +10) + + + 49.00€ O = PIHO - 4.9+ 4.91 = 140 C + / 9.02 2 - > * = 438 mis 4.9 = 0.28 t-Vous = 0.51 see Ry = -4.1 mli x-anis XX. + vt + x = 0 + (438)10.51) + x= 0+14 36 )(0.51)+ 0 = 223.44 m. Horizonte distance will the bullet travelled x = 223.4ml