Answer:
a)
= 3,375 cm
, b) f₀ = 77.625 cm
Explanation:
The magnification of a telescope is, to see at the far point of vision (infinity image)
m = - f₀ / 
The length of the tube is
L = f₀ + 
a) The focal length of the eyepiece
L = - m
+ 
L =
(1-m)
= L / (1-m)
Let's calculate
= 81.0 / (1 - (-23.0)
= 3,375 cm
b) the focal length of the target
f₀ = -m
f₀ = 23 (3.68)
f₀ = 77.625 cm
Explanation:
The emf is equal to the work done on the charge per unit charge (ϵ=dWdq) when there is no current flowing. Since the unit for work is the joule and the unit for charge is the coulomb, the unit for emf is the volt (1V=1J/C).
Red light would be commonly used due to the longer wavelength
Answer:
The bottom of the sea is 25 m below sea level.
Explanation:
Given data
Mass = 6.1 × 

We know that Buoyant force on the tank is equal to gravity force of the tank.



1020 ×
= 6.1 × 
= 598039.21 
We know that
= W × L × H
598039.21 = 300 × 80 × H
H = 25 m
Therefore the bottom of the sea is 25 m below sea level.
To solve this problem we will apply the linear motion kinematic equations. We will find the two components of velocity and finally by geometric and vector relations we will find both the angle and the magnitude of the vector. In the case of horizontal speed we have to



The vertical component of velocity is

Here,
h = Height
g = Gravitational acceleration
t = Time
= Vertical component of velocity



The direction of the velocity will be given by the tangent of the components, then



The magnitude is given vectorially as,



Therefore the angle is 55.59° and the velocity is 26.37m/s