Explanation:
The electric field is defined as the change in the properties of space caused by the existence of a positively (+) or negatively (-) charged particle. The electric field can be represented by infinitely many lines from a particle, and those lines never intersect each other. Depending on the type of charge we can see different cases:
- Let's say we have a <u>positive charge alone (</u>image 1)<u>.</u> The field lines are drawn from the centre of the particle outwards to infinity (in other words, they disappear from the edge of the picture). Meaning the direction of the electric field points outwards the particle.
- For a <u>negative charge alone </u>(image 2)<u>,</u> the lines come from infinity to the centre, and point towards the particle (i.e. lines appear from the edge of the picture).
Let's see what happens if we have two charges together:
- <u>Two positive charges</u> (image 3): Since the charges are of the same type (positive), the particles repel each other. Then the field lines will avoid each other so they do not join. The charge is positive, so lines point outwards.
- <u>Two negative charges</u> (image 4): Again, the charges are both negative, so they repel. But they are negative, so the field points inwards.
- <u>Negative and positive charges</u> (image 5): They are different charges, so the force between them is attractive. This causes the field lines from both to join. They go out of the positive and come into the negative particle.
Image 6:
The lines are passing through infinite points of the space. If we choose a certain point and measure the electric field, we can see to which direction the electric field points. This is the direction of the electric field vector. It does not matter which point we choose; the electric field vector touches the field line only at this point, which means it is tangent to the field line.
Answer:
True
Explanation:
Lose of water content in our body through sweating and lose of essential salts such as potassium and sodium causes heat cramps...
Thank you
Wouldn't you just have to multiply 220 by 1,000,000? That would mean there are 220,000,000 water droplets in one cubic of the cloud.
Answer:
The final temperature of the system is 39⁰C
Explanation:
Applying principle of conservation of heat energy;
Heat loss by a hot body = heat gained by a cold body
![m_hc(T_i_h -T) = m_c(T-T_i_c)](https://tex.z-dn.net/?f=m_hc%28T_i_h%20-T%29%20%3D%20m_c%28T-T_i_c%29)
where;
Mh is the mass of the hot fluid = 330 g = 0.33 kg
Mc is the mass of the cold fluid = 855-g = 0.855 kg
Tih is the initial temperature of the hot fluid = 55°C
Tic is the initial temperature of the cold fluid = 10°C
T is the final temperature of the mixture
Substitute the given values and solve for T
![m_hc(T_i_h -T) = m_c(T-T_i_c)\\\\0.33*4190(55 -T) = 0.855*900(T-10)\\\\1382.7(55 -T) = 769.5(T-10)\\\\(T-10) = 1.797(55 -T)\\\\T-10 = 98.835 - 1.797T\\\\T+ 1.797T = 98.835 + 10\\\\2.797T= 108.835\\\\T = \frac{108.835}{2.797} = 39^o C](https://tex.z-dn.net/?f=m_hc%28T_i_h%20-T%29%20%3D%20m_c%28T-T_i_c%29%5C%5C%5C%5C0.33%2A4190%2855%20-T%29%20%3D%200.855%2A900%28T-10%29%5C%5C%5C%5C1382.7%2855%20-T%29%20%3D%20769.5%28T-10%29%5C%5C%5C%5C%28T-10%29%20%3D%201.797%2855%20-T%29%5C%5C%5C%5CT-10%20%3D%2098.835%20-%20%201.797T%5C%5C%5C%5CT%2B%20%201.797T%20%3D%2098.835%20%2B%2010%5C%5C%5C%5C2.797T%3D%20108.835%5C%5C%5C%5CT%20%3D%20%5Cfrac%7B108.835%7D%7B2.797%7D%20%20%3D%2039%5Eo%20C)
Therefore, the final temperature of the system is 39⁰C
Answer:
Sound intensity levels are quoted in decibels (dB) much more often than sound intensities in watts per meter squared. Decibels are the unit of choice in the scientific literature as well as in the popular media. The reasons for this choice of units are related to how we perceive sounds. How our ears perceive sound can be more accurately described by the logarithm of the intensity rather than directly to the intensity. The sound intensity level β in decibels of a sound having an intensity I in watts per meter squared is defined to be β(dB)=10log10(II0)β(dB)=10log10(II0), where I0 = 10−12 W/m2 is a reference intensity. In particular, I0 is the lowest or threshold intensity of sound a person with normal hearing can perceive at a frequency of 1000 Hz. Sound intensity level is not the same as intensity. Because β is defined in terms of a ratio, it is a unitless quantity telling you the level of the sound relative to a fixed standard (10−12 W/m2, in this case). The units of decibels (dB) are used to indicate this ratio is multiplied by 10 in its definition. The bel, upon which the decibel is based, is named for Alexander Graham Bell, the inventor of the telephone.
Table 1. Sound Intensity Levels and IntensitiesSound intensity level β (dB)Intensity I(W/m2)Example/effect01 × 10–12Threshold of hearing at 1000 Hz101 × 10–11Rustle of leaves201 × 10–10Whisper at 1 m distance301 × 10–9Quiet home401 × 10–8Average home501 × 10–7Average office, soft music601 × 10–6Normal conversation701 × 10–5Noisy office, busy traffic801 × 10–4Loud radio, classroom lecture901 × 10–3Inside a heavy truck; damage from prolonged exposure[1]1001 × 10–2Noisy factory, siren at 30 m; damage from 8 h per day exposure1101 × 10–1Damage from 30 min per day exposure1201Loud rock concert, pneumatic chipper at 2 m; threshold of pain1401 × 102Jet airplane at 30 m; severe pain, damage in seconds1601 × 104Bursting of eardrums