True
In fact, the weight of an object on the surface of the Earth is given by:

where m is the mass of the object and

is the gravitational acceleration on Earth's surface. If we use the mass of the object, m=3.0 kg, we find
Let s = rate of rotation
<span>Let r = radius of earth = 6,400km </span>
<span>Then solving (s^2) r = g will give the desired rate, from which length of day is inferred. </span>
<span>People would not be thrown off. They would simply move eastward in a straight line while the curved surface of earth fell away from beneath them.</span>
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.
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the answer is CaO because that's what my homework says is correct