Answer:1. Find the wavelength in air at 20°C of an ... 19 m. 2. What is the wavelength of an 18-Hz sound wave in seawater at 25°C? ... 3. Find the frequency of a sound wave moving through iron at 25°C with a ... The lowest frequency is. 25. Resonance on Strings A violin sounds a note of F sharp ..
Answer: Option (c) is the correct answer.
Explanation:
The difference in electrical potential energy between two places in an electric field is known as potential difference.
Mathematically, potential difference between two given points can be written as follows.
where, 
= potential difference
= potential at point 1
= potential at point 2
There are 4 forces acting on the block:
• its <u>w</u>eight (magnitude <em>w</em> = <em>m</em> <em>g</em> = 98 N, where <em>m</em> = 10 kg and <em>g</em> = 9.80 m/s²), pointed downward
• the <u>n</u>ormal force (mag. <em>n</em>), pointed upward
• <u>f</u>riction (mag. <em>f</em> = 15 N), pointing opposite the direction of motion
• the <u>p</u>ulling force (mag. <em>p</em> = 75 N), pointing at a 20° angle with the positive horizontal direction
Let the direction in which the block is being pulled be the positive horizontal direction, and upward the positive vertical direction. Split up each force into their horizontal and vertical components, then apply Newton's second law. We have a net horizontal force of
∑ <em>F</em> = <em>p</em> cos(20°) - <em>f</em> = <em>m</em> <em>a</em>
where <em>a</em> is the acceleration of the block. The net vertical force is 0, since the block gets dragged along the surface and doesn't move up or down (presumably).
Solve for <em>a</em> :
(75 N) cos(20°) - 15 N = (10 kg) <em>a</em>
<em>a</em> ≈ 5.4 m/s²
As heat always flows from a higher temperature to a lower temperature, this transfer can go both ways .When the air is cold, warm water will transfer energy to the air and cool off. ... If the air is hot, cold water will receive the energy and warm up.
