Answer:
1. The image of the person is 1.41 m, virtual and formed at the back of the surface of the globe.
2. The person's image is 3.38 m tall.
Explanation:
From the given question, object distance, u = 0.75 m, object height = 1.8 m, radius of curvature of the reflecting globe, r = 8 cm = 0.08 m.
f =
=
= 0.04 m
1. The image distance, v, can be determined by applying mirror formula:
=
+ 
=
+ 
-
= 
= 
= - 
⇒ v = -
= - 1.41 m
The image of the person is 1.41 m, virtual and formed at the back of the surface of the globe.
2.
= 
= 
v = 
= 3.384
v = 3.38 m
The person's image is 3.38 m tall.
The velocity of the board relative to the ice is zero, since both are at rest.
<h3>What is relative velocity?</h3>
Relative velocity is the velocity of an object in relation to another reference object or point.
When two objects are travelling or moving with the same velocity in the same direction, the relative velocity one relative to the other is zero.
Also, when two objects are at rest, the relative velocity one relative to the other is zero.
Therefore, the velocity of the board relative to the ice is zero, since both are at rest.
Learn more about relative velocity at: brainly.com/question/24337516
#SPJ1
Answer: 71.7 KJ
Explanation:
The rotational kinetic energy of a rotating body can be written as follows:
Krot = ½ I ω2
Now, any point on the rim of the flywheel, is acted by a centripetal force, according to Newton’s 2nd Law, as follows:
Fc = m. ac
It can be showed that the centripetal acceleration, is related with the angular velocity and the radius, as follows:
ac = ω2 r
We know that this acceleration has a limit value, so , we can take this limit to obtain a maximum value for the angular velocity also.
As the flywheel is a solid disk, the rotational inertia I is just ½ m r2.
Replacing in the expression for the Krot, we have:
Krot= ½ (1/2 mr2.ac/r) = ¼ mr ac = ¼ 67.0 Kg. 1.22 m . 3,510 m/s2 = 71. 7 KJ
Answer:
c = 5 m
Explanation:
this exercise you want to divide the rectangular room into two triangular rooms
the area of triangles is
A = ½ base height
A = ½ 4 3
A = 6 m²
the length of the curtain can be found using the Pythagorean theorem
c² = b² + a²
c = √ (4² + 3²)
c = 5 m
this is the length of the curtain
Answer:
(orbital speed of the satellite) V₀ = 3.818 km
Time (t) = 4.5 × 10⁴s
Explanation:
Given that:
The radius of the Earth is 6.37 × 10⁶ m; &
the acceleration of gravity at the satellite’s altitude is 0.532655 m/s
We can calculate the orbital speed of the satellite by using the formula:
Orbital Speed (V₀) = √(r × g)
radius of the orbit (r) = 21000 km + 6.37 × 10⁶ m
= (2.1 × 10⁷ + 6.37 × 10⁶) m
= 27370000
= 2.737 × 10⁷m
Orbital Speed (V₀) = √(r × g)
Orbital Speed (V₀) = √(2.737 × 10⁷ × 0.532655 )
= 3818.215
= 3.818 × 10³
= 3.818 Km
To find the time it takes to complete one orbit around the Earth; we use the formula:
Time (t) = 2 π × 
= 2 × 3.14 × 
= 45019.28
= 4.5 × 10 ⁴ s