If the work done on an object doubles its kinetic energy how is the speed of the object

Your grandmother enjoys creating pottery as a hobby. She uses a potter's wheel, which is a stone disk of radius R-0.520 m and ma

Lesechka [4]

Answer:

0.54454

104.00902 N

Explanation:

m = Mass of wheel = 100 kg

r = Radius = 0.52 m

t = Time taken = 6 seconds

$\omega_f$ = Final angular velocity

$\omega_i$ = Initial angular velocity

$\alpha$ = Angular acceleration

Mass of inertia is given by

$I=\dfrac{mr^2}{2}\\\Rightarrow I=\dfrac{100\times 0.52^2}{2}\\\Rightarrow I=13.52\ kgm^2$

Angular acceleration is given by

$\alpha=\dfrac{\tau}{I}\\\Rightarrow \alpha=\dfrac{\mu fr}{I}\\\Rightarrow \alpha=\dfrac{\mu 50\times 0.52}{13.52}$

Equation of rotational motion

$\omega_f=\omega_i+\alpha t\\\Rightarrow \omega_f=\omega_i+\dfrac{\mu (-50)\times 0.52}{13.52}t\\\Rightarrow 0=60\times \dfrac{2\pi}{60}+\dfrac{\mu (-50)\times 0.52}{13.52}\times 6\\\Rightarrow 0=6.28318-11.53846\mu\\\Rightarrow \mu=\dfrac{6.28318}{11.53846}\\\Rightarrow \mu=0.54454$

The coefficient of friction is 0.54454

At r = 0.25 m

$\omega_f=\omega_i+\dfrac{0.54454 (-50)\times 0.52}{13.52}6\\\Rightarrow 0=60\times \dfrac{2\pi}{60}+\dfrac{0.54454 f\times 0.25}{13.52}6\\\Rightarrow 2\pi=0.06041f\\\Rightarrow f=\dfrac{2\pi}{0.06041}\\\Rightarrow f=104.00902\ N$

The force needed to stop the wheel is 104.00902 N

5 0

3 years ago

A reaction mixture in a 3.67 L flask at a certain temperature initially contains 0.763 g H2 and 96.9 g I2, At equilibrium, the f

Alexxandr [17]

Answer:

13 530 482

Explanation:

H2 + I2 ------> 2HI

start (mol) 0.3785 0.3818 0

change (mol) -0.3534 -0.3534 +0.7067

equilibrium (mol) 0.0251 0.0284 0.7067

concentra (mol/L) 0.0068 0.0077 0.1926

$K_{c} = \frac{0.1926^{2}}{0.0068^{2}*0.0077^{2} } = 13530482$

7 0

3 years ago

If a sound wave travels 680 m in 2 seconds and has a frequency of 400 hz, what is the wavelength of the wave?

Kipish [7]

Answer: 0.85 meters (with and without sigfigs)

Explanation: To find the wavelength, you just have to switch around the equation for wave speed: v (wave speed) = λ (wavelength)*f (frequency) so λ (wavelength) = v (wave speed)/f (frequency). You don't have the wave speed but you can calculate it. Since wave speed is measured in meters/second or m/s, you just have to divide the amount of meters you were given by the amount of seconds. You will get 340 m/s. Next, you have to plug the values into the equation: λ (wavelength) = 340 m/s (wave speed)/400 Hz (frequency). The answer is 0.85 meters (seconds cancel) and has the correct number of significant figures.

5 0

3 years ago

Match the block to its correct density. 1. Block A 0.64 Kg/L 2. Block B 0.917 kg/L 3. Block C 0.70 Kg/L 19.3 kg/L 4. Block D 3.5

Sedbober [7]

Answer:

quit school aghahahha

Explanation:

xD

4 0

3 years ago

In 2013, the world record depth for free diving without assistance was 101 m. What is the pressure in the water (assumed freshwa

serg [7]