All categories

3 years ago

A salt shaker sits 0.102 m from

Physics

1 answer:

Ivahew [28]3 years ago

6 0

The maximum speed is 0.55 m/s

Explanation:

For an object in uniform circular motion, the force of friction between the object and the ground provides the centripetal force required to keep the body in motion. Therefore we can write:

$\mu_s mg = m\frac{v^2}{r}$

where the term on the left is the frictional force and the term on the right is the centripetal force, and where

$\mu_s$ is the coefficient of static friction

m is the mass of the body

g is the gravitational acceleration

v is the speed of the body

r is the radius of the circular path

In this problem, we have:

$\mu_s = 0.307$

r = 0.102 m

$g=9.8 m/s^2$

Substituting and re-arranging, we find the maximum speed v at which the salt shaker can rotate:

$v=\sqrt{\mu gr}=\sqrt{(0.307)(9.8)(0.102)}=0.55 m/s$

Learn more about circular motion:

brainly.com/question/2562955

brainly.com/question/6372960

#LearnwithBrainly

You might be interested in

This city is the capital of the state of Georgia since 1868 and was burned during the Civil War.

Sphinxa [80]

The correct answer is - Atlanta.

Georgia is a state that has had multiple capitals since the arrival of the first European settlers, changing them very often in accordance to the circumstances. The last one in the row has been Atlanta. This city got the privilege to be the capital of Georgia in 1868 after the Atlanta council applied for it. The US government took everything in perspective, from infrastructure, population, location, and very importantly politics. The political aspect seems to be the case where Atlanta won the case to become capital, as the capital until than, Milledgeville, was still a city where the black population was not welcomed and the racism was still on a very high level.

3 0

3 years ago

Read 2 more answers

A projectile is shot horizontally at 23.4 m/s from the roof of a building 55.0 m tall. What is the time necessary for the projec

baherus [9]

The horizontal speed has no effect on the answer.

It doesn't matter whether you flick a marble horizontally from the roof,
fire a high-power rifle horizontally from the roof, drive a school bus straight
off the roof, or drop a bowling ball from the roof with zero horizontal speed.
Their vertical speed is completely determined by gravity, (and it happens to
be the same for all of them).

Handy dandy formula for the distance covered by anything that starts out
with zero speed and accelerates to the end:

      Distance = (1/2) (acceleration) x (time)²

If the beginning of the journey is on Earth, then the acceleration is
9.8 m/s² ... the acceleration of gravity on Earth. We'll assume that
the 55-meter rooftop in the question is part of a building on Earth.

   55 meters = (1/2) (9.8 m/s²) x (time)²

Divide each side
by 4.9 m/s² : 55 m / 4.9 m/s² = (time)²

   (time)² = (55/4.9) sec²

Square-root
each side: time = √(55/4.9 sec²)

   =    3.35 sec .

5 0

3 years ago

A bullet of 5 gm is fired from a pistol of 1.5 kg. If the recoil velocity of pistol is 1.5 m/s,

Andreyy89

Answer:

-450 m/s

Explanation:

Momentum is conserved.

p₀ = p

0 = (1.5 kg) (1.5 m/s) + (0.005 kg) v

v = -450 m/s

6 0

3 years ago

Having difficulty finding the PE and KE for these values no mass is given. Does anyone know to go solve these?

Alexandra [31]

11) $1.04\cdot 10^7 J$

12) $1.04\cdot 10^7 J$

13) 50.0 m/s

14) 41.6 m/s

Explanation:

11)

The potential energy of an object is the energy possessed by the object due to its position relative to the ground. It is given by

$PE=mgh$

where

m is the mass of the object

g is the acceleration due to gravity

h is the height relative to the ground

Here in this problem, when the train is at the top, we have:

m = 8325 kg (mass of the train + riders)

$g=9.8 m/s^2$ (acceleration due to gravity)

h = 127 m (height of the train at the top)

Substituting,

$PE=(8325)(9.8)(127)=1.04\cdot 10^7 J$

12)

According to the law of conservation of energy, the total mechanical energy of the train must be conserved (in absence of friction). So we can write:

$KE_t + PE_t = KE_b + PE_b$

where

$KE_t$ is the kinetic energy at the top

$PE_t$ is the potential energy at the top

$KE_b$ is the kinetic energy at the bottom

$PE_b$ is the potential energy at the bottom

The kinetic energy is the energy due to motion; since the train is at rest at the top, we have

$KE_t=0$

Also, at the bottom the height is zero, so the potential energy is zero

$PE_b=0$

Therefore, we find:

$KE_b=PE_t=1.04\cdot 10^7 J$

13)

The kinetic energy of an object is the energy of the object due to its motion. Mathematically, it is given by

$KE=\frac{1}{2}mv^2$

where

m is the mass of the object

v is the speed of the object

From question 12), we know that the kinetic energy of the train at the bottom is

$KE=1.04\cdot 10^7 J$

We also know that the mass is

m = 8325 kg

Therefore, we can calculate the speed of the train at the bottom:

$v=\sqrt{\frac{2KE}{m}}=\sqrt{\frac{2(1.04\cdot 10^7)}{8325}}=50.0 m/s$

14)

At the top of the second hill, the total mechanical energy of the train is still conserved.

Therefore, we can write again:

$KE_1 + PE_1 = KE_2 + PE_2$

where

$KE_1$ is the kinetic energy at the top of the 1st hill

$PE_1$ is the potential energy at the top of the 1st hill

$KE_2$ is the kinetic energy at the top of the 2nd hill

$PE_2$ is the potential energy at the top of the 2nd hill

From the previous questions, we know that

$KE_1=0$

and

$PE_1=1.04\cdot 10^7 J$

The height of the second hill is

h = 39 m

So we can also find the potential energy at the second hill:

$PE_2=mgh=(8325)(9.8)(39)=3.2\cdot 10^6 J$

So, the kinetic energy at the second hill is

$KE_2=PE_1-PE_2=1.04\cdot 10^7 - 3.2\cdot 10^6 =7.2\cdot 10^6 J$

And so, the speed is

$v=\sqrt{\frac{2KE_2}{m}}=\sqrt{\frac{2(7.2\cdot 10^6)}{8325}}=41.6 m/s$

4 0

3 years ago

Sandi believes that people who eat at McDonald's are overweight, so she decides to do a naturalistic observation of people who e

lubasha [3.4K]

Answer:

observer bias

Explanation:

Based on the information provided within the question the thing that should concern us the most about Sandi's observations is Observer Bias. This term refers to the tendency of a researcher to see what they want as opposed to what is actually happening. This can be said because of Sandi's belief that McDonald clients are all overweight, by having this belief before actually having come to this conclusion with a series of tests, it might lead her to believe this to be true regardless of what she observes during the experiment.

I hope this answered your question. If you have any more questions feel free to ask away at Brainly.

6 0

3 years ago