Friction Multiple Choice Questions(MCQs) & Answers

1 Which of the following statements is true for flat belts?

A They are used for short distances between the pulleys

B They have high efficiency

C They are used in lathe machines

D All of the above

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Answer: They are used in lathe machines

2 Which formula is used to calculate angle of static friction (Φs)?

A tan-1 μs

B sin-1 μs

C cos-1 μs

D none of the above

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Answer: tan-1 μs

3 Which of the following surfaces will offer the least friction?

A Vinyl floor

B Plywood

C Plastic

D Ice

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Answer: Ice

4 Tyres of which vehicles are biggest treads among the following?

A Race car

B Car

C Motorbike

D Excavator

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Answer: Excavator

5 The radius of friction circle is independent of

A Weight of the shaft

B Radius of the shaft

C Coefficient of friction

D All of the above

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Answer: Weight of the shaft

6 The flat pivot bearing is used to bear

A Axial Thrust

B Radial Thrust

C Both Radial And Axial Thrust

D None Of The Above

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Answer: Axial Thrust

7 In plate clutch, the clutch plate is placed

A Before flywheel

B After pressure plate

C In between pressure plate and flywheel

D None of the above

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Answer: In between pressure plate and flywheel

8 For a single started thread, the lead is equal to

A p/2

B p

C 2p

D p/3

View Answer

Answer: p

9 When the two surfaces in contact have a very thin layer of lubricant in between them, it is known as

A Solid friction

B Rolling friction

C Greasy friction

D Film friction

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Answer: Film friction

10 The coefficient of friction (µ) is equal to

A TanΦ

B SinΦ

C CotΦ

D All above

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Answer: TanΦ

11 The body will move only when

A Force of friction = applied force

B Force of friction < applied force

C Force of friction > applied force

D All of the above

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Answer: Force of friction < applied force

12 A train has to negotiate a curve of radius 400m. By how much should the putter rail be raised with respect to inner rail for speed of 48 km/h? The distance between the rails is 1m.

A 0.20m

B 0.0454m

C 0.45m

D 0.020m

View Answer

Answer: 0.0454m

13 The force of friction depends upon

A Nature of surface of contact

B Material of objects in contact

C Both ‘a’ and ‘b’

D None of the above

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Answer: Both ‘a’ and ‘b’

14 When moving along a curved path, he

A Leans inwards

B Leans outwards

C Is still

D Leans sideways

View Answer

Answer: Leans inwards

15 Friction can be increased by

A Using air cushion

B Lubricants

C Using sand

D Using ball bearings

View Answer

Answer: Using sand

16 A scooter weighs 120kg f. Brakes are applied so that wheels stop rolling and start skidding. Find the force of friction if the coefficient of friction is 0.4.

A 60kg f

B 48kg f

C 25kg f

D 32kg f

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