Answer:
6.0 m/s
Explanation:
According to the law of conservation of energy, the total mechanical energy (potential, PE, + kinetic, KE) of the athlete must be conserved.
Therefore, we can write:

or

where:
m is the mass of the athlete
u is the initial speed of the athlete (at the bottom)
0 is the initial potential energy of the athlete (at the bottom)
v = 0.80 m/s is the final speed of the athlete (at the top)
is the acceleration due to gravity
h = 1.80 m is the final height of the athlete (at the top)
Solving the equation for u, we find the initial speed at which the athlete must jump:

Power = Work Done / Time taken
Where Work Done is Joules, and Time is in Seconds, Power is in Watts
= 2400 J / 6 seconds
= 400 Watts
The power output is 400 Watts.
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
<h3>Answer</h3>
a. 8J
b. 90J
<h3>Notes formula</h3>
W = F × s
W = Work done (J)
F = Force (N)
s = distance (m)
<h3>Known that </h3>
a. F = 4N
s = 2m
b. F = 30N
s = 3m
<h3>Question</h3>
a. W = ..?
b. W = ..?
<h3>Way to do it</h3>
a. W = F × s
= 4N × 2m = 8J
b. W = F × s
= 30N × 3m = 90J
<em>#Moderators please don't be mean, dont delete my answers just to get approval from your senior or just to get the biggest moderation daily rank.</em>
Answer:
b) 1500N
c) to the right
Explanation:
Resultant force= 2000 -500= 1500N
Resultant force is a combination of 2 or more forces acting on an object.