How do you know when motion has occurred?

If the coefficient of friction is 0.3900 and the cylinder has a radius of 2.700 m, what is the minimum angular speed of the cyli

Aleks04 [339]

Answer:

w=3.05 rad/s or 29.88rpm

Explanation:

k = coefficient of friction = 0.3900

R = radius of the cylinder = 2.7m

V = linear speed of rotation of the cylinder

w = angular speed = V/R or to rewrite V = w*R

N = normal force to cylinder

N= $=\frac{m(V)^{2}}{R}=m*(w)^2*R$

$Friction force\\Ff = k*N\\Ff= k*m*w^2*R$

$Gravitational force \\Fg = m*g$

These must be balanced (the net force on the people will be 0) so set them equal to each other.

$Fg = Ff$

$m*g = k*m*w^2*R$

$g=k*w^{2}*R$

$w^2 =\frac{g}{k*R}$

$w=\sqrt{\frac{g}{k*R}} \\w =\sqrt{\frac{9.8\frac{m}{s^{2}}}{0.3900*2.7m}}\\ w=\sqrt{9.306}=3.05 \frac{rad}{s}$

There are 2*pi radians in 1 revolution so:

$RPM=\frac{w}{2\pi }*60\\RPM=\frac{3.05\frac{rad}{s}}{2\pi}*60\\RPM= 0.498*60\\RPM=29.88$

So you need about 30 RPM to keep people from falling out the bottom

7 0

4 years ago

A crane lifts up two boxes.<br><br> Which free body diagram shows the forces acting on block A?

Temka [501]

Answer:

The 3rd graph

Explanation:

A free body diagram is a diagram which shows all the forces acting on an object.

The problem asks us to find the free body diagram of block A, so we must find all the forces acting on block A.

We have 3 forces acting on block A in total:

- The force of gravity (its weight), which pushes the block downward (in the diagram, it is the force represented with $F_{gA}$

- The tension in the rope 1, which pulls block A upwards: this force is represented with $F_{T1}$

- The tension in the rope 2, due to the weight of block 2, which pulls block A downwards: this force is represented with $F_{T2}$

Based on the direction of these 3 forces, the correct diagram is the 3rd one.

7 0

3 years ago

Read 2 more answers

13. A ball is dropped. According to Newton's Third Law, the action force is the

katrin2010 [14]

Answer:

the ground when the ball hits it

Explanation:

A ball falls freely towards the Earth. If the action force is the Earth pulling down on the ball, then identify which of the following best describe the reaction force:

8 0

3 years ago

What are the fundamental units involved in pascal<br>

Llana [10]

Answer:

<h2>FUNDAMENTAL UNITS INVOLVED ARE : NEWTON AND SECOND .</h2>

<h2>FORMULA OF PRESSURE = </h2>

4 0

4 years ago

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An arrow is shot at an initial velocity of 224 ft/sec from a height of 44 feet, ay what time will the arrow be 824 feet above th

Bingel [31]

The arrow is subject to the constant downward pull of gravity, so its vertical position over time is given by

$y=44\,\mathrm{ft}+\left(224\,\dfrac{\mathrm{ft}}{\mathrm s}\right)t+\dfrac12\left(-32.1\,\dfrac{\mathrm{ft}}{\mathrm s^2}\right)t^2$

We want to find $t$ for which $y=824\,\mathrm{ft}$ . You should find two solutions at $t=6.67\,\mathrm s$ and $t=7.29\,\mathrm s$ .

7 0

4 years ago