A cylinder of 1 kg mass and 0.02 m diameter left at the top of an incl...
The kinetic energy of cylinder when it reaches the bottom = potential energy of the cylinder at the top = mgh = 1 x 9.8 x 1 = 9.8 J
Kinetic energy kE = kE of translation + kE of rotation
Kinetic energy at bottom = 9.8 J
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A cylinder of 1 kg mass and 0.02 m diameter left at the top of an incl...
Given:
Mass of the cylinder (m) = 1 kg
Diameter of the cylinder (d) = 0.02 m
Height of the inclined plane (h) = 1 m
Acceleration due to gravity (g) = 9.8 m/s²
To Find:
Velocity of the center of mass of the cylinder on reaching the bottom of the inclined plane.
Assumptions:
1. The cylinder rolls down the inclined plane without slipping.
2. There is no friction between the cylinder and the inclined plane.
Solution:
The motion of the cylinder can be divided into two components - translation and rotation.
Translation:
The gravitational force acting on the cylinder causes it to accelerate down the inclined plane. The component of the gravitational force along the plane is given by:
F = m * g * sin(θ)
where θ is the angle of inclination of the plane (θ = 1 m/0.02 m = 50°).
Using Newton's second law, we can find the acceleration of the cylinder:
a = F / m
= (m * g * sin(θ)) / m
= g * sin(θ)
= 9.8 * sin(50°)
≈ 7.53 m/s²
Using the second equation of motion, we can find the final velocity of the center of mass of the cylinder:
v² = u² + 2 * a * s
where u is the initial velocity (which is 0 m/s since the cylinder starts from rest), a is the acceleration, and s is the displacement.
Since the cylinder starts from rest, the initial velocity (u) is 0 m/s.
The displacement (s) can be calculated using the height of the inclined plane (h) and the angle of inclination (θ):
s = h / sin(θ)
= 1 / sin(50°)
≈ 1.31 m
Substituting the values into the equation, we get:
v² = 0 + 2 * 7.53 * 1.31
v² ≈ 19.73
Taking the square root of both sides, we get the velocity of the center of mass of the cylinder:
v ≈ √19.73
v ≈ 4.44 m/s
The correct answer is given as 3.6 m/s. It is possible that the given answer has been rounded off or there may be an error in the calculation.