Answer:
44J
Explanation:
Given parameters:
Mass of rock = 0.22kg
Initial velocity = 20m/s
Distance moved = 10m
Unknown:
Initial kinetic energy of the rock = ?
Solution:
To solve this problem, we need to understand that kinetic energy is the energy due to the motion of a body.
It is mathematically expressed as;
Kinetic energy = 
m v²
m is the mass
v is the velocity
Kinetic energy = x 0.22 x 20² = 44J
Position of paul with respect to john is given as
14 m due west of john
position of George with respect to Paul is given as 36 m in direction 37 degree south of east
now we need to find the position of George with respect to John
![r_{GJ} = r_G - r_j[\tex]now for the above equation we can add the two equations[tex]r_{Gj} = -14\hat i + 36 cos37\hat i - 36sin37\hat j](https://tex.z-dn.net/?f=r_%7BGJ%7D%20%3D%20r_G%20-%20r_j%5B%5Ctex%5D%3C%2Fp%3E%3Cp%3Enow%20for%20the%20above%20equation%20we%20can%20add%20the%20two%20equations%3C%2Fp%3E%3Cp%3E%5Btex%5Dr_%7BGj%7D%20%3D%20-14%5Chat%20i%20%2B%2036%20cos37%5Chat%20i%20-%2036sin37%5Chat%20j)
so the magnitude is given as
and direction is given as
<em>so it is 26.2 m at an angle 55.75 degree South of east</em>
A diverging lens is used to permit clear vision of an object placed at infinity. The focal length of the lens is -100 cm.
<h3>What is focal length?</h3>
The focal length is half of the radius of curvature of the focal lens.
By the lens maker formula,
1/f = 1/v +1/u
where, v is the image distance and u is the object distance.
Give, the object is at infinity and the image must form at 100 cm, the the focal length will be
1/f = 1/ -100 + 1/∞
f = -100 cm
The focal length must be -100 cm for the diverging lens.
Learn more about focal length.
brainly.com/question/16188698
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High frequency for the range of radio frequency electronmagnetic waves between 3 and 30 megahertz (MHz)
