Answer:
Thrust due to fuel consumption must overcome gravitational force from the Earth to send the rocket up into space.
Explanation:
From the concept of Escape Velocity, derived from Newton's Law of Gravitation, definition of Work, Work-Energy Theorem and Principle of Energy Conservation, which is the minimum speed such that rocket can overcome gravitational forces exerted by the Earth, and according to the Tsiolkovski's Rocket Equation, which states that thrust done by the rocket is equal to the change in linear momentum of the rocket itself, we conclude that thrust due to fuel consumption must overcome gravitational force from the Earth to send the rocket up into space.
Weight = (mass) x (acceleration of gravity at the place where the mass is) .
Man's mass = 80 kg
His weight on Earth = (80 kg) x (9.8 m/s²) = 784 newtons (about 176 pounds)
His weight on the Moon = (80 kg) x (1.63 m/s²) = <em>130.4 newtons</em> (about 29.2 pounds)
His mass is <em>80 kg</em>. Mass is the thing about him that doesn't change.
He has the same mass on the Earth, on the Moon, or anywhere.
Answer: C. A rubber eraser
Answer:
Energy needed = 54.02 J
Explanation:
the Energy in an elastic spring from hookes law is given as
F= ke , therefore the energy (E) is
E = 
K = 19.5 N/cm
e = 1.39cm
E = 
x 19.5 x 1.39
E = 13.55 J
The energy to stretch the spring for 6.93cm is
E = x 19.5 x 6.93
E = 67.57 J
The more energy needed for the further stretch is
67.57 - 13.55
Energy needed = 54.02 J
