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
Answer:

Explanation:
Net force by which man push the lawn mower is given as

now it is given that 37% of this force is vertically downwards
so we will have


now we also know that

here we have


Now work done by this force to move the lawn mower is given as



Answer:
1.8 m/s
Explanation:
Draw a free body diagram of the block. There are four forces:
Normal force Fn up.
Weight force mg down.
Applied force F to the east.
Friction force Fn μ to the west.
Sum the forces in the y direction:
∑F = ma
Fn − mg = 0
Fn = mg
Sum the forces in the x direction:
F − Fn μ = ma
F − mg μ = ma
a = (F − mg μ) / m
a = (12 N − 6 kg × 9.8 m/s² × 0.15) / 6 kg
a = 0.53 m/s²
Given:
Δx = 3 m
v₀ = 0 m/s
a = 0.53 m/s²
Find: v
v² = v₀² + 2aΔx
v² = (0 m/s)² + 2 (0.53 m/s²) (3 m)
v = 1.8 m/s
Answer:
true
Explanation:
Reflection is when light bounces off an object. If the surface is smooth and shiny, like glass, water or polished metal, the light will reflect at the same angle as it hit the surface. ... This is called diffuse reflection. Diffuse reflection is when light hits an object and reflects in lots of different directions.
Force = mass x acceleration
Mass is given to be 250kg
Acceleration is given to be 5m/s^2
Force = 250kg x 5m/s^2 = 1,250 kgm/s^2 = 1,250 Newtons