The Lee family has installed energy efficient appliances and lightbulbs in their home. What effect can they expect to see?

A 89.3 kg horizontal circular platform rotates freely with no friction about its center at an initial angular velocity of 1.77 r

balu736 [363]

Answer:

$\omega_{2} = 1.107\,\frac{rad}{s}$

Explanation:

Let assume that circular platform is a solid cylinder. Given the absence of external forces, the situation can be analyzed by applying the Principle of Angular Momentum, which states that:

$I_{1}\cdot \omega_{1} = I_{2}\cdot \omega_{2}$

The initial moment of inertia is:

$I_{1} = \frac{1}{2}\cdot (89.3\,kg)\cdot (1.69\,m)^{2}$

$I_{1} = 127.525\,kg\cdot m^{2}$

Likewise, the final moment of inertia is:

$I_{2} = 127.525\,kg\cdot m^{2} + (8.83\,kg)\cdot (1.352\,m)^{2} + (21.1\,kg)\cdot (1.69\,m)^{2}$

$I_{2} = 203.929\,kg\cdot m^{2}$

The final angular speed is:

$\omega_{2} = \frac{I_{1}}{I_{2}} \cdot \omega_{1}$

$\omega_{2} = \frac{127.525\,kg\cdot m^{2}}{203.929\,kg\cdot m^{2}} \cdot (1.77\,\frac{rad}{s} )$

$\omega_{2} = 1.107\,\frac{rad}{s}$

4 0

3 years ago

Read 2 more answers

HELP PLS! :/

zlopas [31]

Explanation:

formula: Vi = Vf - (at)

Vi: intial velocity

Vf: final velocity

a: acceleration

t: time

fill in formula with the numbers you are given

Vi= 41.6m - ((9.81 m/s^2)(1.89s))

parenthesis first according to pemdas

Vi= 41.6m - 18.54m/s

Answer: 23.06m/s

disclaimer: I havent done physics in awhile so I have no idea if this is right. just an attempt to help steer you in the right direction hopefully. good luck

7 0

3 years ago

help i am confused about this riddle.IF NOTHING IS FASTER THAN LIGHT HOW DID THE DARK GET THERE FIRST

vodka [1.7K]

Answer:

because darkness is the absence of light, so that means darkness was there before the light came! :)

Explanation:

5 0

3 years ago

Read 2 more answers

A force F acts at one corner of a thin, square metal plate. The force acts in the same plane as the plate. Which dashed line rep

Delvig [45]

The image of the thin square metal plate showing the force and the lines are missing, so i have attached it.

Answer:

Line B represents the lever arm

Explanation:

From the attached image, we can see 4 different dashed lines between the force F and the moment centroid O.

Now, we want to know which of the dashed lines represents lever arm.

Now, in physics/engineering, the lever arm which is also known as moment arm is defined as the perpendicular distance between the line of action of the acting force and the centre of the moments.

Now, from the image attached, the only dashed line that is perpendicular to the acting Force F and the moment centre O is Line B.

Thus,line B represents the lever arm