Answer:
5.33 cm
Explanation:
The lens equation states that:
where
f is the focal length
p is the distance of the object from the lens
q is the distance of the image from the lens
In this problem,
p = 8 cm
q = 16 cm ( the sign is positive since the image is real, which means it is formed on the other side of the lens)
Substituting into the equation,
Answer:
Explanation:
You have to declare which way is plus -- up or down. I will use down.
vi = - 2.85 The balloon is going up. That is the minus direction.
a = 9.81
d = 2.50 meters distance in this case is from the object to the ground.
d = vi*t + 1/2 a t^2
-2.50 = -2.85*t + 1/2 * 9.81 * t^2
-2.50 = -2.85*t + 4.905 * t^2 transfer the left to the right.
-4.905 t^2 + 2.85*t + 2.50 = 0
Use the quadratic formula to solve for t.
It turns out that t = 1.06