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An object is placed on an incline where the coefficient of kinetic friction is

0.20. If the mass of the object is 25 kg, how long does it take to slide down the 3.5 m incline
if the angle of inclination is 30°? The object begins moving at the top of the incline, from rest.

1 Answer

4 votes

The time it will take the object to slide down the incline is determined as 2.03 s.

How to calculate the time of motion?

The time it will take the object to slide down the incline is calculated as follows;

s = ut + ¹/₂at²

where;

  • u is the initial velocity of the object
  • t is the time of motion
  • a is the acceleration of the object
  • s is the distance traveled
  • θ is the angle of inclination

s = 0 + ¹/₂at²

s = ¹/₂at²

s = ¹/₂(μg cosθ)t²

t² = 2s / μg cosθ

t = √ ( 2s / μg cosθ )

The time it will take the object to slide down the incline is calculated as follows;

t = √ ( 2s / μg cosθ )

t = √ ( 2 x 3.5 / (0.2 x 9.8 x cos 30 )

t = 2.03 s

User Enrico Murru
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