(a) 147,500 J
Newton's second law, applied to the helicopter, states that
where
F is the lifting force
mg is the weight of the helicopter, with m=500 kg being the mass of the helicopter and g=9.8 m/s^2 the acceleration due to gravity
a=2.00 m/s^2 is the acceleration of the helicopter
From the equation, we can calculate the magnitude of the lifting force:
The vertical distance covered by the helicopter is given by
So, the work done by the lifting force F is
2) -122,500 J
The magnitude of the gravitational force acting on the helicopter is
And the work done by this force on the helicopter is
And the negative sign is due to the fact that the direction of the gravitational force is opposite to the displacement of the helicopter.
3) 25,500 J
The net work done on the helicopter is given by the sum of the work done by the two forces:
Answer:
149.34 Giga meter is the distance d from the center of the sun at which a particle experiences equal attractions from the earth and the sun.
Explanation:
Mass of earth = m =
Mass of Sun = M = 333,000 m
Distance between Earth and Sun = r = 149.6 gm = 1.496\times 10^{11} m[/tex]
1 giga meter =
Let the mass of the particle be m' which x distance from Sun.
Distance of the particle from Earth = (r-x)
Force between Sun and particle:
Force between Sun and particle:
Force on particle is equal:
F = F'
= ±577.06
Case 1:
x =
Acceptable as the particle will lie in between the straight line joining Earth and Sun.
Case 2:
x =
Not acceptable as the particle will lie beyond on line extending straight from the Earth and Sun.
1000/48 is 20.83 so the answer would be 20.83 meters/second
increase air resistance, which decreases gravitational acceleration
Kepler's third law of planetary motion states that:
"The ratio between the cube of the orbital radius of the planet and the square of the orbital period is constant". In formulas:
where r is the orbital radius and T the orbital period.
Since this ratio is constant for every planet, we see that when the orbital radius r is larger (i.e. when the planet is farther from the Sun), the orbital period T is larger: this means the planet takes more time to complete one revolution around the Sun, so it moves slower.
Therefore, the correct option is:
<span>A planet moves slowest when it is farthest from the sun.</span>