Semi-conductors are materials that A) are good conductors. B)allow electron flow and resist neutron flow. c)have insulator and conductor properties. d)allow neutron flow. Semi-conductors are materials that have insulator and conductor properties.

A. The change in kinetic energy is –345.075 J

B. The amount of work done is –345.075 J

C. The cart travelled a distance of 34.51 m

ΔKE = ½m(v² – u²)

ΔKE = ½ × 15 × (3.2² – 7.5²)

ΔKE = 7.5 × –46.01

ΔKE = –345.075 J

The workdone in this case is equal to the change in energy of the cart.

Wd = Fd

Divide both side by F

d = Wd / F

d = –345.075 / –10

d = 34.51 m

Learn more about energy:

https://brainly.com/question/10703928

Answer: Option A

Explanation: The buoyant force depends on the amount of displaced fluid (in this case water)

As the wood is less dense than the iron, the wood requires a lot less upwards force to float, and it only displaces a little bit of fluid, in the other case, the iron requires a lot more of force to do it, so it displaces a lot of water and is totally submerged, and the iron block can never float actually, so it sinks down, at the point that the buoyant force applied is negative (the weight of the water upside the block is bigger than the force upwards)

The Buoyant force can be calculated as:

B = weight on-air - weight on water.

The block of wood is floating, so the weight on the water is zero, and the buoyant force is equal to his weight in the air.

For the block of  iron, we have:

B = Weight on-air - weight on water, here in both cases we have positive numbers, but not enough information to know them.

Then the only information that we have is that the woodblock displaces less water than the other block, so with this, we only can know that the buoyant force in the woodblock is smaller.

The SI unit of power is the watt (W), which is equivalent to 1 joule per second (1 J/s). Power indicates the rate at which work is performed or energy converted, and it can also be expressed in horsepower (hp), where 1 hp equals 746 W.

The SI unit of power is the watt (W). Power, in physics, represents the rate at which work is performed or energy is converted. The definition of a watt is 1 joule per second (1 W = 1 J/s), meaning that when one watt of power is expended, one joule of energy is used every second. Additionally, power can be expressed in horsepower (hp), where 1 hp is equivalent to 746 W. This unit is commonly used to indicate the power output of engines and motors.

Electric power is specifically measured in watts as well, and electric energy is measured in joules. However, for practical purposes such as billing, energy companies use the kilowatt-hour (kWh), which measures the total energy used over a period of time.

If the sun shrank in size but its mass remained the same, the Earth's orbit around the Sun would remain unchanged. This is due to the fact that it's the Sun's mass, not its size, that mainly determines the strength of its gravitational pull on Earth.

If the sun were to shrink in size but maintain the same mass, the gravitational pull it exerts on the Earth would remain the same. This is based on Newton's law of universal gravitation, which states that two bodies attract each other with a force proportional to the product of their masses and inversely proportional to the square of the distance between their centers. Therefore, if the sun's mass is unchanged, the Earth's orbit would remain unchanged as well because it is the sun's mass (not its size) that principally determines the strength of its gravitational pull on the Earth.

https://brainly.com/question/35880093

#SPJ12

In kinematics, motion equations are derived using the time interval, Δt, between events. Before the concept of special theory of relativity came to be, everyone thought that the time interval, Δt, is the same for every observer, whether the observer is at rest or in motion. This is called absolute time.

However, according to Einstein, time is not absolute; that is, the time interval, Δt, depends upon the velocity of the observer

The weightlifter used approximately 833.33 Watts of power to lift the barbell.

To calculate the power used by the weightlifter to lift the barbell, we need to first determine the work done and then divide it by the time taken to do this work. Power is defined as work done per unit time.

The work ( W ) done when lifting the barbell can be calculated using the formula W = force (F) x distance (d). In this case, the force is equal to the weight of the barbell (1,250 N) and the distance is 2 meters, so the work done would be:

W = F x d = 1,250 N x 2 m = 2,500 Joules

Now, the power ( P) can be calculated using the formula P = W / time ( t). The time taken to lift the barbell is 3 seconds, so:

P = W / t = 2,500 J / 3 s = 833.33 Watts

Therefore, the weightlifter used approximately 833.33 Watts of power to lift the barbell.

The light intensity at 2.0 m from the bulb would be I0/4. The rms magnetic field value at 2.0 m from the bulb would be B0/2. The average energy density of the waves at 2.0 m from the bulb would be u0/4.

1. The light intensity follows the inverse square law, which means that the intensity decreases as the distance squared increases. So at 2.0 m from the bulb, the light intensity would be I0/4.

2. The rms magnetic field value is related to the light intensity through the equation B0 = sqrt((2u0cI0)/(ε0c^2)), where c is the speed of light and ε0 is the vacuum permittivity. Therefore, at 2.0 m from the bulb, the rms magnetic field value would be B0/sqrt(4) = B0/2.

3. The average energy density of the waves is equal to the energy per unit volume. It can be calculated using the formula u0 = ε0E0^2/2, where E0 is the rms electric field value. At 2.0 m from the bulb, the average energy density of the waves would be u0/4.

https://brainly.com/question/29561338

#SPJ11

At 2.0 m from the 60-W light bulb, the light intensity is one-fourth of the intensity at 1.0 m, the RMS magnetic field value is half of the initial value, and the average energy density also becomes one-fourth of the initial value.

To solve the problem involving a 60-W light bulb radiating electromagnetic waves:

Answer:

The height of the cliff is found to be 176.4 m

Explanation:

Since, the body is being dropped from a certain height and reaches the ground in some time. Thus, we can apply the equations of motion (modified for vertical motion) in this case, due to constant accelerated motion. We have the following data:

Acceleration due to gravity = g = 9.8 m/s²

Time to reach ground = t = 6 sec

Initial Velocity of the Rock = Vi = 0 m/s (Because, the rock will be at rest, initially)

Height of cliff = H = ?

Now, applying second equation of motion (modified for vertical motion), to the rock, between the top of the cliff and ground, we get:

H = Vi t + (1/2)gt²

Using values:

H = (0 m/s)(6 sec) + (1/2)(9.8 m/s²)(6 sec)²

H = 176.4 m

Answer: Yes

Explanation: The definition of displacement is the change on the position, So if i start in my home, then i go to the mall, and after that i return home, the total displacement over that period of time is 0, because i started in my house and ended in my house. But in that proces i traveled the distance between my house and the mall two times. So is possible to travel great distances without any displacement, only if the endpoint of the travel is the same as the start point.

A 4000kg truck is parked on a 15.0∘ slope, the friction force on the truck is approximately 10,293 N.

We must take into account the truck's weight and the slope's angle in order to calculate the friction force on a truck that is parked on a hill.

The following formula can be used to determine the truck's weight:

Weight = mass × gravitational acceleration

Weight = 4000 kg × 9.8 m/s²

= 39,200 N

Parallel Component = Weight × sin(angle)

The angle of the slope is given as 15.0 degrees. Converting this to radians, we get:

Angle in radians = 15.0 degrees × (π/180)

≈ 0.2618 radians

Now we can calculate the parallel component:

Parallel Component = 39,200 N × sin(0.2618)

≈ 10,293 N

Therefore, the friction force on the truck is approximately 10,293 N.

For more details regarding friction force, visit:

https://brainly.com/question/13707283

#SPJ6

Answer:

False

Explanation: Lightening is not an example of matter in solid or liquid state. It is a phenomenon of spark of electricity in the atmosphere. Lightening can also be seen in volcanic eruptions,forest fires, thunderstorms, hurricanes etc. In the initial stage of development of lightening air acts as an insulator between positive and negative charge but when charge develops enough it break the wall of insulator air and sparking occurs.

The difference in heat, q, between the two processes cannot be determined without additional information, such as the specific heat capacities or the number of moles of gas. Since the final temperature is the same, the difference in work done relates to the difference in heat q due to the first law of thermodynamics, but exact values require further data.

To determine the difference between q for the two-step process and q for the one-step process, we need to apply the principles of thermodynamics. Since the gas is ideal, we can use the formula q = nCΔT, where n is the number of moles, C is the molar heat capacity, and ΔT is the change in temperature. However, since the final temperature is the same for both processes, ΔT will be the same, implying that the heat exchange, q, is simply dependent on the pathway taken by the process.

In the two-step process, the work done is the sum of the work in each step. According to the formula W = -PΔV (work done by the gas is negative when compressed), the external pressure multiplied by the change in volume gives us the work. Since the work done by the gas is different in the two-step and one-step processes, the heat q will also differ according to the first law of thermodynamics, which states that the change in internal energy is equal to the heat added to the system plus the work done on the system (ΔU = q + W).

Given that the final internal energy is the same in both cases because the final temperature is the same, the difference in work done between the processes will equal the difference in heat exchanged. However, without specific heat capacities or the amount of substance (moles), we cannot calculate the exact difference in q.

The answer is 15.0 mL

The energy transformations chart that take place when energy from the wind is used to generate electricity is  best completed by kinetic energy transformed to mechanical energy.

Wind power, also known as wind energy, is the use of wind turbines to generate electricity. Wind energy is a popular, sustainable, renewable energy source that has a much lower environmental impact than burning fossil fuels.

Wind power has historically been used in sails, windmills, and wind pumps, but it is now primarily used to generate electricity. Wind farms are made up of many individual wind turbines that are linked to an electric power transmission network.

Hence, kinetic energy of wind transforms mechanical energy of the turbines in wind power stations.

Learn more about wind power here:

https://brainly.com/question/13266865

#SPJ6

Final answer:

When a 10-newton force is applied to a 2-kg block and the block slides across the floor at a constant speed of 5 m/s, we can conclude that the applied force is balanced by the frictional force acting on the block.

Explanation:

From the given information, we can conclude that the applied 10-newton force is balanced by the frictional force acting on the block. This is because the block slides at a constant speed of 5 m/s, indicating that the net force on the block is zero. The frictional force is equal in magnitude and opposite in direction to the applied force. Therefore, we can infer that the magnitude of the frictional force is also 10 newtons. This situation demonstrates Newton's first law of motion, which states that an object will remain at rest or move with constant velocity unless acted upon by an external force.