A block of 50 N weight rests in limiting equilibrium on rough incline...
Given data:
- Weight of the block, W = 50 N
- Slope of the inclined plane initially, θ1 = 30°
- Slope of the inclined plane after raising, θ2 = 60°
- Force required to move the block up, F = ?
Analysis:
To calculate the force required to move the block up the inclined plane, we need to consider the forces acting on the block. These forces include:
1. Weight of the block (mg), acting vertically downwards.
2. Normal force (N), acting perpendicular to the inclined plane.
3. Frictional force (f), acting parallel to the inclined plane.
Step 1: Resolving Forces:
We can resolve the weight of the block into two components:
- The component perpendicular to the inclined plane (mg*cosθ), which is balanced by the normal force (N).
- The component parallel to the inclined plane (mg*sinθ), which is balanced by the frictional force (f).
Step 2: Equating Forces:
In limiting equilibrium, the frictional force (f) is given by the equation:
f = μN
where μ is the coefficient of friction.
Since the block is just about to move up the inclined plane, the frictional force (f) will be at its maximum value, which is given by:
f(max) = μ(max) * N
where μ(max) is the maximum coefficient of friction.
Step 3: Determining the Maximum Coefficient of Friction:
The maximum coefficient of friction is given by:
μ(max) = tan(θ)
where θ is the angle of the inclined plane.
Step 4: Calculating the Force Required:
Substituting the value of μ(max) into the equation for the frictional force (f(max)) gives:
f(max) = μ(max) * N
f(max) = tan(θ) * N
Since the frictional force (f) is equal to the force required to move the block up (F), we have:
F = f(max) = tan(θ) * N
Step 5: Calculation:
Substituting the given values of θ and N into the equation for the force required (F), we get:
F = tan(60°) * N
F = tan(60°) * 50 N
F ≈ 57.74 N
Therefore, the force required to move the block up the inclined plane is approximately 57.74 N.
A block of 50 N weight rests in limiting equilibrium on rough incline...
R = W cos 60° ...(1)
F = W sin 60° + μR ...(2)
From equation (1) and (2) we get
= 57.74 N
To make sure you are not studying endlessly, EduRev has designed Mechanical Engineering study material, with Structured Courses, Videos, & Test Series. Plus get personalized analysis, doubt solving and improvement plans to achieve a great score in Mechanical Engineering.