Answer:
The change in gravitational potential energy of the climber-Earth system is 
Explanation:
From the question we are told that
The mass of the hiker is 
The time taken is 
The vertical elevation after time T is 
The change in gravitational potential is mathematically represented as

here g is the acceleration due to gravity with value
substituting values


Explanation:
Geocentric model said that the Earth is at the center of the universe and everything revolves around it. It was considered to be stationary. Galileo proved this model incorrect with the help of his astronomical observations. Some of the key observation that he used to support the heliocentric model were:
1. He proposed the theory that the tides on the Earth occur because of its motion.
2. He observed the phases of the Venus which meant that the Venus revolved around the Sun and not the Earth.
3. He observed other planets and thus noted that they also move around the Sun and not Earth.
4. He discovered the Moons of other planets.
Answer:
How high the sound or how low the sound is depending on the pitch of the sound which in this case the frequencies of the sound. The higher of the frequencies , the higher of the pitch but it has the shortest length of wave (λ). That's why AM radio have a longer range but bad audio quality than FM radio that have better audio quality with shorter range.
Solution :
Speed of the air craft,
= 262 m/s
Fuel burns at the rate of,
= 3.92 kg/s
Rate at which the engine takes in air,
= 85.9 kg/s
Speed of the exhaust gas that are ejected relative to the aircraft,
=921 m/s
Therefore, the upward thrust of the jet engine is given by

F = 85.9(921 - 262) + (3.92 x 921)
= 4862635.79 + 3610.32
= 
Therefore thrust of the jet engine is
.