a brand of a lightbulb has a power of 55w and an efficiency of 1.6% how much power is wasted as heat by this lightbulb

If my mass is 196 lbm and I tackle one of my teammates - while decelerating from a velocity of 6.7 m/s to 0 m/s in 0.5 s, how mu

Olin [163]

Answer:

the force acting on the team mate is 1.19 kN.

Explanation:

given,

mass = 196 lbm

while tackling, the deceleration is from velocity 6.7 m/s to 0 m/s

time taken for deceleration = 0.5 sec

F = mass × acceleration

acceleration = $\dfrac{0-6.7}{0.5}$

= -13.4 m/s²

1 lbs = 0.453 kg

196 lbs = 196 × 0.453 = 88.79 kg

F = 88.79 × 13.4

F = 1189.786 N = 1.19 kN

hence, the force acting on the team mate is 1.19 kN.

8 0

3 years ago

Select the statements that correctly interpret the data in this heating curve.

tekilochka [14]

The consistent temperature indicated by section 2 represents the flow of energy lost as the water freezes.

Section 2 indicates that energy is being utilized to bring all molecules to the melting point.

Section 4 indicates that the temperature is stable until all molecules reach the boiling point.

The increasing temperature in section 5 indicates that molecular motion is increasing.

Explanation:

The figure is missing: find it in attachment.

The graph represents the temperature of a block of ice as heat is continuously supplied to it.

At the beginning (section 1), the temperature increases: in this phase, the heat supplied to the ice is used to increase the kinetic energy of vibration of the molecules of ice.

When the ice reach point A (melting point), the ice starts to melt. In this phase (section 2), the temperature of the substance remains constant, because all the heat supplied is used to break the bonds between the molecules, converting the ice into liquid water.

At point B, the ice has completely melted, and therefore we now have liquid water.

In sector 3 (between B and C), the temperature of the water increases again as we supply more and more heat: this heat, in fact, is used to increase the kinetic energy of the molecules, which move faster and faster.

Then, the water reaches the boiling point (point C): after that, the water starts to boil, (sector 4) and the heat supplied is entirely used to remove the intermolecular forces between the molecules of water; as a result, the temperature remains constant during the process.

At poind D, the water has completely boiled, and converted into gas state (steam).

After that, the temperature of the steam starts to increase again (sector 5) as more and more heat is supplied, because it is used to increase the kinetic energy of the molecules.

Therefore, the correct statements are:

The consistent temperature indicated by section 2 represents the flow of energy lost as the water freezes.

Section 2 indicates that energy is being utilized to bring all molecules to the melting point.

Section 4 indicates that the temperature is stable until all molecules reach the boiling point.

The increasing temperature in section 5 indicates that molecular motion is increasing.

3 0

3 years ago

Read 2 more answers

In a double-slit experiment, the third-order maximum for light of wavelength 490 nm is located 15 mm from the central bright spo

jeka94

Answer:

The distance from the central bright spot are $156.8\times10^{-3}\ mm$ and $142.9\times10^{-3}\ mm$ .

Explanation:

Given that,

Wavelength = 490 nm

Distance y= 15 mm

Length L=1.6 m

New wavelength = 670

We need to calculate the distance from the central bright spot

Using formula of distance

$y= \dfrac{m\lambda L}{d}$

$d=\dfrac{m\lambda L}{y}$

Put the value into the formula

$d=\dfrac{3\times490\times10^{-9}\times1.6}{15\times10^{-3}}$

$d=156.8\times10^{-6}\ m$

$d=156.8\times10^{-3}\ mm$

We need to calculate the distance from the central bright spot for new wavelength

Using formula of distance

$d=\dfrac{m\lambda L}{y}$

Put the value into the formula

$d=\dfrac{2\times670\times10^{-9}\times1.6}{15\times10^{-3}}$

$d=142.9\times10^{-6} m$

$d=142.9\times10^{-3}\ mm$

Hence, The distance from the central bright spot are $156.8\times10^{-3}\ mm$ and $142.9\times10^{-3}\ mm$ .

8 0

3 years ago

Light propagating in air strikes the surface of a lake. The reflected ray makes 62° angle with the normal. What angle does the r

blondinia [14]

Answer:

(a) 42°

Explanation:

According to the law of reflection:

Angle of incidence = Angle of reflection

So, angle of reflection = 62°

Angle of incidence = 62°

For refraction,

Using Snell's law as:

$n_i\times {sin\theta_i}={n_r}\times{sin\theta_r}$

Where,

${\theta_i}$ is the angle of incidence ( 62.0° )

${\theta_r}$ is the angle of refraction ( ? )

${n_r}$ is the refractive index of the refraction medium (water, n=1.33)

${n_i}$ is the refractive index of the incidence medium (air, n=1)

Hence,

$1\times {sin62.0^0}={1.33}\times{sin\theta_r}$

Angle of refraction = $sin^{-1}0.6639$ = 42°

4 0

3 years ago

A sledgehammer hits a wall How do the hammer and the wall act on each other?

tigry1 [53]

We want to study the impact of a sledgehammer and a wall.

Before the sledgehammer hits the wall, it has a given velocity and a given mass, so it has momentum and it has kinetic energy.

When it hits the wall, the velocity of the hammer disappears, this means that the energy is transferred to the wall, this "transfer of energy" can be thought of a force applied for a really short time on the wall, which for the third law of Newton, the force is also applied on the hammer.

This is why you feel the impact on the handle when you hit something with a hammer, this also means that some of the energy is dissipated on your arms.

Now, because the wall is made of a material usually not as strong as the head of the sledgehammer, we will see that in this interaction the wall seems more affected than the hammer, but the forces that each one experiences are exactly equal in magnitude.

If you want to learn more, you can read:

brainly.com/question/13952508

7 0

3 years ago