Science Class 6th

421. In a pulley system, for change of direction, ______ pulley is used.

A. No

B. Additional

C. Both ‘a’ and ‘b

422. In a pulley system, in which 3 pulleys are combined, and three segments of rope support the weight, the effort required will be equal to _______ of the weight lifted.

A. 1/4

B. 1/3

C. 1/5

D. 1/2

423. When function of the pulley is affected because stretching of pulley’s band, we use _________ to restore the function of pulley.

A. Idler pulley

B. Tensioning pulley

C. Both ‘a’ and ‘b’

D. None of these

424. Pulley is commonly used in?

A. Top of flag pole

B. drawing water from well

C. Mast of sailing boats

D. All of the above

425. A_____ is a wheel with teeth that mesh with the teeth of another gear.

A. Gear

B. Wheel

C. None of these

426. A combination of two or more gears constitute __________ system.

A. Wheel

B. Pulley

C. Gear

427. Gear system is used to transmit or receive ___________.

A. Force

B. Motion

C. Both ‘a’ and ‘b’

D. None of these

428. When one gear drives another gear, both the gears move in _______ direction.

A. Same

B. Opposite

C. Some times same

D. All of these

429. If it is needed to turn both the gears in the same direction, a third gear called ______ is introduced between the two gears.

A. Pulley

B. Gear

C. Idler gear

D. All of the above

430. Gear is used in which of the following?

A. Hand food mixer

B. egg beater

C. Saving machines

D. All of these

431. Force is applied on?

A. Driving gear

B. Driven gear

C. None of these

432. _______ turns due to the movement of driving gear.

A. Driving

B. Driven gear

C. None of these

433. Gear can transmit _______ force to another gear in the same or opposite direction.

A. Linear

B. Circulatory

C. Both ‘a’ and’b’

434. The working of gear is determined by?

A. Size

B. Material

C. Teeth

D. Both ‘a’ and ‘c’

435. A force applied on small gear will turn the larger _______ but will have a great force.

A. Slowly

B. Faster

C. None of these

436. A force applied on larger gear will turn a smaller gear ______ but will have less force.

A. Faster

B. Slower

C. None of these

437. The speed of the driven shaft depends on the number ______ in gear.

A. Pulleys

B. Teeth

C. Both ‘a’ and ‘b’

D. None of these

438. A gear with 10 teeth driving, a gear with 20 teeth will revolve _______ as fast as compared to the driving gear.

A. Thrice

B. Twice

C. Never

D. None of these

439. The _______ of gear system can be increased by changing gears during the lifting of any load.

A. Speed

B. Direction

C. Efficiency

D. None of these

440. Which of the following work on the combine motion of gear and pulley systems?

A. Crane

B. Bicycle

C. Wind up clock

D. All of these