<em>Hello, </em>
<h3><u>QUESTION)</u></h3>Assuming that the initial velocity of the jumper is zero, on Earth any freely falling object has an acceleration of 9.8 m/s².
<em>✔ We have : a = v/Δt = ⇔ Δt = v/a </em>
Answer:
Force on the object is 20 N
Explanation:
As we know that work done to raise the book from initial position to final position is known as potential energy stored in it
So here we know that
here we know that
U = 30 J
s = displacement = 1.5 m
so we have
Answer:
The focal length of the lens should be -51.5 cm (a concave lens).
Explanation:
The purpose of the lens is to make objects at 48.5 cm appear at the healthy near point. The healthy near point is 25.0 cm.
We use the lens formula
where <em>f</em> = focal length, <em>u</em> = object distance and <em>v</em> = image distance.
In this case, <em>u</em> = 48.5 cm and <em>v</em> = -25.0 cm.
<em>v</em> is negative because the image is virtual an not real. (Here, we are using the real-is-positive sign convention)
The negative sign indicates the lens is concave.