AUTOMOBILE ENGINEERING MCQ SECTION 24

231. This is the bottom surface joining the sides of two adjacent threads is

(A) Lead

(B) Pitch

(C) Crest

(D) Root

Answer: - Root

232. The units of moment of inertia of mass are

(A) kg m²

(B) m⁴

(C) kg/m²

(D) kg/m

Answer: - kg/m²

233. The ratio of limiting friction and normal reaction is known as

(A) coefficient of friction

(B) angle of friction

(C) angle of repose

(D) sliding friction

Answer: - coefficient of friction

234. Tangent of angle of friction is equal to

(A) kinetic friction

(B) limiting friction

(C) angle of repose

(D) coefficient of friction

Answer: - coefficient of friction

235. The property of a material by virtue of which a body returns to its original, shape after removal of the load is called

(A) plasticity

(B) elasticity

(C) ductility

(D) malleability

Answer: - elasticity

236. The fuel in diesel engine is normally injected at pressure of

(A) 5-10 kg/cm2

(B) 20-25 kg/cm2

(C) 60-80 kg/cm2

(D) 90-130 kg/cm2

Answer: - 90-130 kg/cm²

237. If the temperature of intake air in IC engines is lowered, then its efficiency will

(A) increase

(B) decrease

(C) remain same

(D) increase upto certain limit and then decrease

Answer: - increase

238. Harmful radiation emitted by the sun is

(A) visible

(B) infra-red

(C) ultra-violet

(D) radio waves

Answer: - ultra-violet

239. Which of these is not a renewable source of energy ?

(A) The sun

(B) Natural gas

(C) Wind

(D) Ocean tidal energy

Answer: - Natural gas

240. In diesel engine the diesel fuel injected into cylinder would burn instantly at about compressed air temperature of

(A) 250°C

(B) 500°C

(C) 1000°C

(D) 150°C

Answer: - 1000°C