A Styrofoam slab has thickness h and density ρs. When a swimmer of mass m is resting on it, the slab floats in fresh water with its top at the same level as the water surface. Find the area of the slab. (Use any variable or symbol stated above along with the following as necessary: ρw for the density of water.)

Answer:

B) Copper atoms have loosely held free electrons in their outer shell that is able to move freely in other atoms.

Explanation:

A material which has loosely held free electrons in its outermost shell is always a good conductor. These loosely held free electrons move from atoms to atoms and cause conductivity. It is known that copper and other metals are good conductors. Therefore, option (B) supports the argument and is a right answer.

Answer: His average speed (in m/s) for the race was 10.08 m/s

Explanation:

Given data

Total distance traveled , D= 100 meter

Total time taken , T= 9.92 seconds

>The average speed([tex]V_{avg}[/tex] ) of an object is the total distance traveled by the object divided by the total time taken to cover that distance .i.e.,

[tex]V_{avg}=\frac{D}{T}=\frac{100}{9.92}\, \frac{m}{s}=10.08\: \frac{m}{s}[/tex]

Thus his average speed (in m/s) for the race was 10.08 m/s

Answer A. Red shift. verified 12/21/18 per test results.

Answer:

Speed

Explanation:

The information "100 miles per hour" describes that the train travels 100 miles of distance in a time period of 1 hour. we know that the speed is defined as the distance traveled by an object in unit interval of time with no information about the direction of motion. hence the information "100 miles per hour" about the express train describes the speed of the train.

By definition, the gravitational force is given by:

[tex] F = G(\frac{m1m2}{r^2}) [/tex]

Where,

G: gravitational constant

m1: mass of object 1

m2: mass of object 2

r: distance between objects:

We know that the force is equal to 10N:

[tex] G(\frac{m1m2}{r^2}) = 10 [/tex]

If the distance is double we have:

[tex] F = G(\frac{m1m2}{(2r)^2}) = G(\frac{m1m2}{4r^2}) = \frac{1}{4}G(\frac{m1m2}{r^2}) [/tex]

[tex] \frac{1}{4}(10) = 2.5 [/tex]

Therefore, the new force is:

2.5 newtons

Answer:

the changed force of attraction between them is:

A. 2.5 newtons

Answer:

v = 4.66 inch/s

Explanation:

As we know that the height of the rod and the distance from the fisherman is related to each other as

[tex]x^2 + y^2 = L^2[/tex]

now differentiate it with respect to time

[tex]2x\frac{dx}{dt} + 0 = 2L\frac{dL}{dt}[/tex]

here we know that

[tex]\frac{dL}{dt} = 4 inch/s[/tex]

now when

x = 20 ft  and y = 12 ft then the length of the line is given as

[tex]L^2 = 12^2 + 20^2[/tex]

[tex]L = 23.3 ft[/tex]

now from above relation

[tex]\frac{dx}{dt} = \frac{L}{x}(\frac{dL}{dt})[/tex]

now we have

[tex]v_x = \frac{23.3}{20} (4 inch/s)[/tex]

[tex]v_x = 4.66 inch/s[/tex]

Transmission

Final answer:

The linear speed of a point on a 3.5-inch floppy disk rotating at 31.4 rad/s is calculated using the formula v = r⋅ω, resulting in a linear speed of 1.396 m/s.

Explanation:

The question is about determining the linear speed of a point on a 3.5-inch floppy disk that rotates with an angular speed. The linear speed v can be calculated using the formula v = r⋅ω, where r is the radius of the disk and ω is the angular speed. Given the diameter of the disk is 3.5 inches, we must first convert it to the radius in meters which is 0.04445 meters (since 1 inch = 0.0254 meters). Therefore, the linear speed is v = 0.04445 m × 31.4 rad/s = 1.396 m/s.

sewage is the answer because it's what the water was filled with most

Answer:

F = 100 N

Explanation:

Since the wagon is pulled along the inclined plane upwards so here the component of the weight of the wagon will act down the plane.

There is no friction force on the wagon so here in order to move the wagon upwards along the plane we require a force along the plane upwards which must be of same magnitude as that the magnitude of weight along the plane downwards.

now the component of weight along the inclined is given as

[tex]F = Wsin\theta[/tex]

[tex]F = 200 sin30[/tex]

[tex]F = 200(0.5) [/tex]

[tex]F = 100 N[/tex]

To pull a 200 N wagon up a 30-degree incline at constant speed, a parallel force of 100 N is needed. This calculation assumes no friction. It is derived using the component of the gravitational force parallel to the incline.

To determine the force needed to pull a 200 N wagon up a 30-degree incline at a constant speed, we need to analyze the components of the gravitational force acting on the wagon.

Therefore, a force of 100 N parallel to the incline is needed to pull the wagon up at a constant speed, assuming no friction.

Before answering this question, first we have to understand the effect of ratio of surface area to volume on the rate of diffusion.

The rate of diffusion for a body having larger surface area as compared to the ratio of surface area to volume will be more than a body having less surface area. Mathematically it can written as-

                           V∝ R            [ where v is the rate of diffusion and r is the ratio of surface area to volume]

As per the question,the ratio of surface area to volume for a sphere is given [tex]0.08m^{-1}[/tex]

The surface area to volume ratio for right circular cylinder is given [tex]2.1m^{-1}[/tex]

Hence, it is obvious that the ratio is more for right circular cylinder.As the rate diffusion is directly proportional to the surface area to volume ratio,hence rate of diffusion will be more for right circular cylinder.

Hence the correct option is B. The rate of diffusion would be faster for the right cylinder.

If the gas in a sealed container has a pressure of 50 kPa at 300 K, so the pressure if the temperature rises will be 60 kPa.

The physical force applied to an object is referred to as pressure. A perpendicular force is applied to the surfaces of the objects per unit area. The basic formula for pressure is F/A. (Force per unit area). Pressure is measured in Pascals (Pa).

There are several types pressure of them are Atmospheric Pressure, Gauge pressure, Differential Pressure, and Absolute pressure.

According to the question,

PV=nRT

P/T=nR/V

P/T= constant

Therefore,

(P/T)1=(P/T)2

50/100=P2/360

P2=50×(360/300)

P2= 60 kPa.

Hence, the pressure P2 is 60 kPa.

To get more information about pressure :

https://brainly.com/question/12977546

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Final answer:

The student's question requires estimating the rate of change of the turkey's temperature after cooling for an hour, which is determined by the slope of the tangent on the temperature graph. This mathematical concept also has a real-life application in ensuring that turkey is cooked to a safe internal temperature of 165°F using a food thermometer.

Explanation:

The student's question involves calculating the rate of change of the turkey's temperature after allowing it to cool for an hour. To accomplish this, one would measure the slope of a tangent line drawn on the graph at the point corresponding to one hour post removal from the oven. The slope of the tangent represents the rate at which the turkey's temperature is changing at that specific time—essentially, how quickly it is approaching room temperature.

While this problem is primarily mathematical, it involves knowledge about cooking temperatures as context. This includes knowing the safe internal temperatures for various meats—a roast turkey should reach a safe minimum internal temperature of 165°F to ensure it is safe to consume. The mathematics involved in graphing and calculating slopes can help in ensuring that these safety standards are followed by providing precise information about how quickly the food is cooling and when it has reached a safe temperature.

When using a food thermometer to check for these safe temperatures, the concepts of rates of change are at work as the thermometer relays how quickly the internal temperature is reaching the desired heat level. This practical application shows the importance of mathematical concepts in everyday life.

The estimated rate of change of the temperature of the turkey after an hour is about -10°F per minute, indicating it is cooling down.

Understanding the Concept of Rate of Change:
The rate of change of temperature is represented by the slope of the tangent line on the graph at a specific time. In this case, after one hour, we can look at the graph to find the corresponding temperature and its change over a small time interval.

Finding the Slope at t = 1 hour:  

The slope of the tangent line at a point on a graph is calculated using the formula:
[tex]\text{slope} = \frac{\Delta y}{\Delta x}[/tex]
where [tex]\Delta y[/tex] is the change in temperature and [tex]\Delta x[/tex] is the change in time.

Locate the point on the graph that corresponds to 1 hour after placing the turkey on the table. Let's say the temperature at that point is roughly 150°F (you would need to confirm this from the actual graph).

Let's assume that right before the 1-hour mark (at approximately 59 minutes), the temperature was about 160°F.

Calculate the Change:  

Change in temperature:
[tex]\Delta y = y_1 - y_0 = 150 - 160 = -10 \text{ F}[/tex]  

Change in time:
[tex]\Delta x = 60 - 59 = 1 \text{ minute}[/tex]

Calculate the Slope:  

Now apply the values into the slope formula:
[tex]\text{slope} = \frac{\Delta y}{\Delta x} = \frac{-10 \, \text{F}}{1 \, \text{min}} = -10 \, \text{F/min}[/tex]

Answer: The answer is 2. Prohibited the Chinese laborers from entering the country.

Explanation: The Chinese Exclusion Act of 1882 was a federal law in the United States signed by President Chester. It effectively halted Chinese immigration. I hope your answer is very helpful, please mark me as Brainliest and have a wonderful day! :D

The speed of the ball just before impact is calculated using the conservation of energy principle, translating the potential energy into kinetic energy and solving for velocity to obtain 5.60 m/s.

The speed of the ball just before impact on the building site, we can make use of the principle of conservation of energy. Initially, when the ball is held at a height, it possesses potential energy. When released, this potential energy is converted into kinetic energy just before impact. Given the height it falls through, we can calculate its final speed using the equation for potential energy (PE) and kinetic energy (KE):

PE = KE at the point of release and just before impact,

mgh = ½ mv²,

where m is the mass of the ball, g is the acceleration due to gravity (approximately 9.81 m/s²), h is the height, and v is the final speed. After rearranging and solving for v, we get v = √(2gh).

Inserting the values: v = √(2 * 9.81 m/s² * 1.6 m) = √(31.392) = 5.60 m/s. Therefore, the speed of the ball just before impact is approximately 5.60 meters per second.

Answer:

8.0 m/s

Explanation:

By the law of conservation of momentum, the total momentum before the collision must be equal to the total momentum after the collision:

[tex]p_i=p_f[/tex]

The total momentum before the collision is given only by the momentum of the first sphere, since the second sphere is stationary (so its speed is zero and its momentum is zero as well):

[tex]p_i = m_1 u_1 =(80.0 g)(20.0 m/s)=1600 g m/s[/tex]

The total momentum after the collision is given only by the momentum of the second sphere, since the first sphere completely stops, so:

[tex]p_f = m_2 v_2[/tex]

Using conservation of momentum, we find

[tex]p_i=m_2 v_2\\1600 g m/s = (200.0 g) v_2 \\v_2 = \frac{1600 g m/s}{200.0 g}=8.0 m/s[/tex]

The second sphere moves away with a speed of 8 m/s after the collision, derived using the principle of conservation of momentum

To determine the speed of the second sphere after the collision, we need to use the principle of conservation of momentum. According to this principle, the total momentum before the collision is equal to the total momentum after the collision.

Given:

After the collision, the first sphere stops completely. Therefore, its final velocity (v'1) is 0 m/s.

The total momentum before the collision:

After the collision, let the velocity of the second sphere be v'2.

The total momentum after the collision:

Since momentum is conserved, pinitial = pfinal:

Thus, after the collision, the second sphere moves away with a speed of 8 m/s.

The absolute error and % error in the measurement of equivalent resistance are :

Electrical circuits can generally be divided into two types , i.e :

In series circuit, the electric current flowing on each resistor is always the same as the total current.

To find the total resistances you can use the following formula:

[tex]\large {\boxed {R_s = R_1 + R_2 + R_3 + ...} }[/tex]

In parallel circuits, the electrical voltage at each resistor is always the same as the source voltage.

To find the total resistances you can use the following formula:

[tex]\large {\boxed {\frac{1}{R_p} = \frac{1}{R_1} + \frac{1}{R_2} + \frac{1}{R_3} + ...} }[/tex]

Let's tackle the problem now !

Given:

[tex]R_1 = 100 \pm 3 ~ Ohm[/tex]

[tex]R_2 = 200 \pm 4 ~ Ohm[/tex]

Unknown:

Absolute Error = ?

% Error = ?

Solution:

[tex]R_s = R_1 + R_2[/tex]

[tex]R_s = ( 100 \pm 3 ) + ( 200 \pm 4 )[/tex]

[tex]\large {\boxed {R_s = 300 \pm 7 ~ Ohm} }[/tex]

[tex]\frac{1}{R_p} = \frac{1}{R_1} + \frac{1}{R_2}[/tex]

[tex]\frac{1}{R_p} = \frac{R_2}{R_1 ~ R_2} + \frac{R_1}{R_2 ~ R_1}[/tex]

[tex]\frac{1}{R_p} = \frac{R_1 + R_2}{R_1 ~ R_2}[/tex]

[tex]R_p = \frac{R_1 ~ R_2}{R_1 + R_2}[/tex]

[tex]R_p = \frac{100 \times 200}{100 + 200}[/tex]

[tex]R_p = \frac{20000}{300}[/tex]

[tex]R_p = \frac{200}{3} ~ Ohm[/tex]

[tex]R_p \approx 67 ~ Ohm[/tex]

To find the % Error , we will use this following formula :

[tex]\frac{\Delta R_p}{R_p} = \frac{\Delta R_1}{R_1} + \frac{\Delta R_2}{R_2} + \frac{\Delta (R_1 +R_2)}{R_1 + R_2}[/tex]

[tex]\frac{\Delta R_p}{R_p} = \frac{3}{100} + \frac{4}{200} + \frac{7}{300}[/tex]

[tex]\frac{\Delta R_p}{R_p} = \frac{11}{150}[/tex]

[tex]\frac{\Delta R_p}{R_p} = \frac{11}{150} \times 100{\%}[/tex]

[tex]\frac{\Delta R_p}{R_p} \approx 7{\%}[/tex]

[tex]Absolute ~ Error = \Delta R_p[/tex]

[tex]Absolute ~ Error = \frac{11}{150} \times \frac{200}{3}[/tex]

[tex]Absolute ~ Error = \frac{44}{9}[/tex]

[tex]Absolute ~ Error \approx 5 ~ Ohm[/tex]

[tex]\large {\boxed {R_p = 67 \pm 5 ~ Ohm} }[/tex]

Grade: High School

Subject: Physics

Chapter: Current of Electricity

Keywords: Series , Parallel , Measurement , Absolute , Error , Combination , Resistor , Resistance , Ohm

Answer:

Ultraviolet radiation  

Explanation:

Apex

The camera takes approximately 2.02 seconds to reach the ground after being released by the parachutist, and just before hitting the ground, the velocity of the camera is approximately 29.8 m/s.

To solve for the time it takes for the camera to reach the ground (A) and the velocity of the camera before it hits the ground (B), we can use the equations of motion under the influence of gravity. Assuming the acceleration due to gravity (g) is 9.8 m/s², and the initial velocity of the camera (u) is 10 m/s (since it's released in free fall by the parachutist moving downward at this speed).

Part A: Time to Reach the Ground

We use the equation: s = ut + 0.5gt², where s is the distance (50m), u is the initial velocity, and t is the time in seconds. Plugging in the values, we get:

50 = 10t + 0.5*9.8*t²

Solving this quadratic equation for t, we find that the time taken for the camera to reach the ground is approximately 2.02 seconds.

Part B: Velocity Before Hitting the Ground

The final velocity (v) can be found using the equation: v = u + gt. Substituting u = 10 m/s, g = 9.8 m/s², and t = 2.02s:

v  = 10 + 9.8*2.02 ≈ 29.8 m/s

Therefore, the velocity of the camera just before it hits the ground is approximately 29.8 m/s.

The claim that lava blown out of a volcano is called pumice is False; pumice is a volcanic rock formed from cooling lava with trapped gas, not the lava itself.

The statement that lava blown out of a volcano in an explosive eruption is called pumice is False. Pumice is not lava itself, but rather a type of volcanic rock that forms when frothy lava cools and solidifies with a high volume of gas bubbles trapped inside. Pumice is a vesicular felsic igneous extrusive rock that is light enough to float on water due to its numerous gas bubble cavities giving it a very low density.

Pumice is characterized by a frothy texture and typically takes on a whitish, light grayish, or very light brown color. Most notably, pumice has a high porosity because of the many gas bubbles that were present in the originating lava. While pumice results from volcanic eruptions, it is the solid portion that forms from rapidly cooling lava with trapped gas bubbles, distinguishing it from molten lava ejected during an eruption.

In the context of volcanic fragmental rocks such as tuff, pumice fragments can be found within a light-colored volcanic ash. These rocks are formed by explosive volcanic eruptions that blast solid fragments and ash into the atmosphere.

Answer:

c. They both have a high energy output.

Explanation:

- Nuclear fusion is the process in which two lighter nuclei combine together into a heavier nucleus

- Nuclear fission is the process in which a heavier nucleus breaks apart into smaller nuclei

In both cases, a huge amount of energy is released. In fact:

- In the nuclear fusion, the mass of the heavier nucleus is slightly lower than the sum of the masses of the two initial nuclei: this means that part of the initial mass has been converted into energy, according to the equation

[tex]E=mc^2[/tex]

and we can see that even for small amount of mass, m, the energy released is huge

- In the nuclear fission, the mass of the final products is less than the mass of the initial heavier nucleus, so again, part of the initial mass has been converted into energy, according to the equation

[tex]E=mc^2[/tex]

a.  They both require a high energy input.  No.  Fission doesn't require ANY energy input to get going.  

b.  They both occur without byproducts.   No.  The by-products of fission are the biggest real problem in commercial nuclear power . . . where to put the bad stuff that's left over.

c.  They both have a high energy output.  Yes !

d.  They both involve large atoms breaking into smaller atoms.  No.  'Fission' involves large nucleii breaking into smaller ones.  'Fusion' is exactly the opposite ... combining small nucleii into more complex ones.

Answer:

If the velocity of a car is halved, the centripetal force required to keep it in path of constant radius becomes one fourth of the initial force.

Explanation:

The centripetal force is required to move an object in circular path. Mathematically, the formula of the centripetal force is given by :

[tex]F=\dfrac{mv^2}{r}[/tex]

Here,

m is the mass of the object

v is the velocity of object

r is the radius of the circular path

If the velocity of the car is halved, v'=v/2

New centripetal force is given by :

[tex]F'=\dfrac{mv'^2}{r}[/tex]

[tex]F'=\dfrac{1}{4}\times \dfrac{mv^2}{r}\\\\F'=\dfrac{1}{4}\times F[/tex]

New centripetal force becomes one fourth of the initial force, when the velocity of a car is halved.

Final answer:

When the velocity of a car is halved, the centripetal force required to keep it in a path of constant radius is divided by four.

Explanation:

When the velocity of a car is halved, the centripetal force required to keep it in a path of constant radius is divided by four. This is because the centripetal force is directly proportional to the square of the velocity and inversely proportional to the radius of the circular path.

For example, let's say the original velocity of the car is v and the centripetal force required is F. When the velocity is halved to v/2, the centripetal force becomes (v/2)² = F/4.

Therefore, the centripetal force required to keep a car in a path of constant radius is divided by four when the velocity is halved.

Answer:

C .Nebula

Explanation:

Protostar is an early stage in the formation of a star. Main sequence star is formed after the protostar heats up to almost 10 million kelvin temperature.

The interstellar medium fills the entire space, which appears to be seemingly empty. It is comprised of gas and dust. Hydrogen is the most abundant element in this medium, which is spread across and fills the space.

Under the influence of gravity, pressure and temperature, these clouds of gas and dust come together forming nebula. Hydrogen and helium in this nebula, under high temperature  conditions form protostars.