What is the primary cause of **slip** in belt drives?
A
Belt material B
Pulley alignment C
Insufficient friction between belt and pulley D
Too much tension
Analysis & Theory
Slip occurs due to low friction between the belt and pulley surfaces.
What is the effect of slip in a belt drive system?
A
Increases velocity ratio B
Improves power transmission C
Reduces velocity ratio and efficiency D
Increases pulley diameter
Analysis & Theory
Slip leads to loss of motion, reducing the actual velocity ratio and transmission efficiency.
Which formula gives the **length of an open belt drive**?
A
L = π(R + r) + 2C + (R + r)² / 4C B
L = π(R + r)/2 + 2C + (R - r)² / 4C C
L = 2π(R - r) + 2C D
L = π(R - r)/2 + C
Analysis & Theory
Open belt: L = π(R + r)/2 + 2C + (R - r)² / 4C
What is the main difference between open and cross belt drives?
A
Open belts rotate pulleys in opposite directions B
Cross belts reduce slip C
Cross belts rotate pulleys in opposite directions D
Open belts are longer
Analysis & Theory
In a cross belt drive, pulleys rotate in opposite directions.
Which formula gives the **length of a cross belt drive**?
A
L = π(R + r)/2 + 2C + (R - r)² / 4C B
L = π(R + r)/2 + 2C + (R + r)² / 4C C
L = π(R - r)/2 + 2C D
L = π(R + r) + 2C
Analysis & Theory
Cross belt: L = π(R + r)/2 + 2C + (R + r)² / 4C
If the slip is 5% and driver runs at 1000 RPM, what is the driven pulley speed?
A
950 RPM B
1000 RPM C
1050 RPM D
500 RPM
Analysis & Theory
Slip reduces speed: N2 = N1 × (1 - slip%) = 1000 × 0.95 = 950 RPM