ExamVeda
Login
Home

A flywheel on a motor goes from rest to 1000 rpm...

This question belongs to Mechanical Engineering Engineering Mechanics
Engineering Mechanics
?

A flywheel on a motor goes from rest to 1000 rpm in 6 sec. The number of revolutions made is nearly equal to

Answer & Solution
Correct Answer: Option B
Let's discuss the solution. Join the discussion
Examveda
Question posted by Examveda
Community

Join the Discussion

3 Comments
Agha Sherazi
Agha Sherazi 5 years ago
Intial angular velocity , ω₀ = 0 [because flywheel moves from rest ]
final angular velocity, ω = 1000 rpm = 1000/60 rev/sec
Time taken , t = 6 sec

We know, the formula,
ω = ω₀ + αt
Where α is angular acceleration.
1000/60 = 0 + α6
α = 1000/360 = 100/36 = 25/9 rev/s²

Now, use formula
θ = ω₀t + 1/2αt²
= 0 + 1/2 × 25/9 × (6)²
= 1/2 × 25/9 × 36
= 1/2 × 25 × 4
= 50 rev
Firoz Khan
Firoz Khan 7 years ago
Ans : v = u + at
1000/60 = 0 + 6a
a = 2.78
S = ut +. 5at^2
= 0 +. 5 * 2.78 * 36
= 50
Infinite Knowledge
Infinite Knowledge 7 years ago
How to get the answer?
Keep Learning

Related Questions on Engineering Mechanics

The resultant of two equal forces P making an angle $$\theta ,$$ is given by
A. $$2{\text{P}}\sin \frac{\theta }{2}$$ B. $$2{\text{P}}\cos \frac{\theta }{2}$$ C. $$2{\text{P}}\tan \frac{\theta }{2}$$ D. $$2{\text{P}}\cot \frac{\theta }{2}$$
A framed structure is perfect, if the number of members are __________ (2j - 3), where j is the number of joints.
A. Equal to B. Less than C. Greater than D. None of these
If a number of forces are acting at a point, their resultant is given by
A. $${\left( {\sum {\text{V}} } \right)^2} + {\left( {\sum {\text{H}} } \right)^2}$$ B. $$\sqrt {{{\left( {\sum {\text{V}} } \right)}^2} + {{\left( {\sum {\text{H}} } \right)}^2}} $$ C. $${\left( {\sum {\text{V}} } \right)^2} + {\left( {\sum {\text{H}} } \right)^2} + 2\left( {\sum {\text{V}} } \right)\left( {\sum {\text{H}} } \right)$$ D. $$\sqrt {{{\left( {\sum {\text{V}} } \right)}^2} + {{\left( {\sum {\text{H}} } \right)}^2} + 2\left( {\sum {\text{V}} } \right)\left( {\sum {\text{H}} } \right)} $$
The linear acceleration (a) of a body rotating along a circular path of radius (r) with an angular acceleration of $$\alpha $$ rad/s2, is
A. $${\text{a}} = \frac{\alpha }{{\text{r}}}$$ B. $${\text{a}} = \alpha {\text{r}}$$ C. $${\text{a}} = \frac{{\text{r}}}{\alpha }$$ D. None of these
More Related Questions on Engineering Mechanics