Efficiency = (Wanted) energy out ÷ energy in × 100
Energy in = 400J
Wanted Energy out = 240J
Energy cannot be used up, only transferred, so the remaining energy is most likely to be transferred into unwanted energy (loss of energy) such as heat energy.
Efficiency = 240 ÷ 400 × 100
Efficiency = 0.6 × 100
Efficiency = 60%
Answers:
a) 
b) 
Explanation:
a) Since we are told the satellites circle the space station at constant speed, we can assume they follow a uniform circular motion and their tangential speeds
are given by:
(1)
Where:
is the angular frequency
is the radius of the orbit of each satellite
is the period of the orbit of each satellite
Isolating
:
(2)
Applying this equation to each satellite:
(3)
(4)
(5)
(6)
(7)
(8)
Ordering this periods from largest to smallest:

b) Acceleration
is defined as the variation of velocity in time:
(9)
Applying this equation to each satellite:
(10)
(11)
(12)
(13)
(14)
(15)
Ordering this acceerations from largest to smallest:

Answer:
0.68 m
Explanation:
We know that the speed of sound in air is a product of frequency and wavelength. Taking speed of sound in air as 340 m/s
V=frequency*wavelength
Then wavelength is given by 350/500=0.68 m
Therefore, to repeat constructive interference at the listener's ear, a distance of 0.68 m is needed
Answer:
Both, potential energy and kinetic energy depends on mass. The higher the mass, the higher the energy. However, the difference is that potential energy depends on vertical height whereas kinetic energy depends on the velocity.
Explanation:
From the formula we can see that;
Potential Energy = mass* gravitational acceleration *vertical height.
Kinetic Energy = 0.5 * mass * (velocity)^2