Q4
MCQ • 1M
Analytical & Spatial Aptitude
In the given figure, the numbers associated with the rectangle, triangle, and ellipse are 1, 2, and 3, respectively. W hich one among the given options is the most appropriate combination of P, Q, and R ?
Q6
MCQ • 2M
Verbal Aptitude
Column-I has statements made by Shanthala; and, Column -II has responses given by Kanishk. Column-I Column-II P. This house is in a mess. 1. Alright, I won't bring it up during our conversations. Q. I am not happy with the marks given to me. 2. Well, you can easily look it up. R. Politics is a subject I avoid talking about. 3. No problem, let me clear it up for you. S. I don't know what this word means. 4. Don't worry, I will take it up with your teacher. Identify the option that has the correct match between Column-I and Column-II.
Q46
NAT • 2M
Airfoil & Wing Theory
An aircraft is flying at an altitude of 4500 m above sea level, where the ambient pressure, temperature and density are 57 kPa, 259 K and 0.777 kg/m3, respectively. The speed of the aircraft (V) is 230 m/s. Gas constant R= 287 J/kg/K, and specific heat ratio 𝛾 = 1.4. If the stagnation pressure is po, and static pressure is p, the value of [ po-p 1 2𝜌V2 ] is ________ (rounded off to two decimal places).
Q47
NAT • 2M
Atmospheric Flight Mechanics
A rectangular wing of 1.2 m chord length and aspect ratio 5 is tested in a wind tunnel at an air speed of 60 m/s. The density and the dynamic viscosity of air are 1.3 kg/m3 and 1.8×10-5 kg/m-s, respectively. A second rectangular wing of the same span, but with an aspect ratio of 6, is to be tested in the same tunnel at the same Reynolds number. The air speed at which the second test should be performed is _______ m/s (answer in integer).
Q52
NAT • 2M
Space Dynamics & Orbital Mechanics
A jet-powered airplane is steadily climbing at a rate of 10 m/s. The air density is 0.8 kg/m3, and the thrust force is aligned with the flight path. Using the information provided in the table below, the airplane's thrust to weight ratio is ______ (rounded off to one decimal place). Airplane speed 80 m/s Lift coefficient, CL 0.8 Aspect ratio 6 Oswald efficiency factor 0.8 Zero-lift drag coefficient 0.02
Q53
NAT • 2M
Thermodynamic Cycles of Gas Turbines
F and G denote two points on a spacecraft's orbit around a planet, as indicated in the figure. O is the center of the planet, P is the periapsis, and the angles are as indicated in the figure. If OF = 8000 km, OG = 10000 km, 𝜃F = 0 deg, and 𝜃G = 60 deg, the eccentricity of the spacecraft's orbit is ____ (rounded off to two decimal places).
Q54
NAT • 2M
Thermodynamic Cycles of Gas Turbines
While taking off, the net external force acting on an airplane during the ground roll segment can be assumed to be constant. The airplane starts from rest. SLO and VLO are the ground roll distance and the lift-off speed, respectively. 𝛼VLO (𝛼 > 0) denotes the airplane speed at 0.5 SLO. Neglecting changes in the airplane mass during the ground roll segment, the value of 𝛼 is _____ (rounded off to two decimal places).
Q60
NAT • 2M
Strength of Materials & Elasticity
Two designs A and B, shown in the figure, are proposed for a thin-walled closed section that is expected to carry only torque. Both A and B have a semi-circular nose, and are made of the same material with a wall thickness of 1 mm. With strength as the only criterion for failure, the ratio of maximum torque that B can support to the maximum torque that A can support is__ (rounded off to two decimal places).
Q61
NAT • 2M
Thin-Walled Structures
An ideal turbofan with a bypass ratio of 5 has core mass flow rate, ṁ a,c= 100 kg/s. The core and the fan exhausts are separate and optimally expanded. The core exhaust speed is 600 m/s and the fan exhaust speed is 120 m/s. If the fuel mass flow rate is negligible in comparison to ṁ a,c, the static specific thrust (T/ṁ a,c) developed by the engine is ____ Ns/kg (rounded off to the nearest integer).
Q65
NAT • 2M
Aerospace Materials & Fatigue
A single-stage axial compressor, with a 50 % degree of reaction, runs at a mean blade speed of 250 m/s. The overall pressure ratio developed is 1.3. Inlet pressure and temperature are 1 bar and 300 K, respectively. Axial velocity is 200 m/s. Specific heat at constant pressure, Cp = 1005 J/kg/K and specific heat ratio, γ = 1.4. The rotor blade angle at the outlet is ___ degrees (rounded off to two decimal places).