True! A lightyear is the distance that light travels in a year. The light from the supernova would take 25 years to travel 25 lightyears to Earth for us to see.
Answer:
G = 1.670 ×
Explanation:
From Newton's law of universal gravitation,
F =
Where F is the force of attraction, G is the gravitational constant, M is the mass of the earth, R is the radius of the earth.
From Newton's second law of motion,
F = mg
mg =
g =
⇒ G =
If the radius of the earth becomes half,
R = , then;
G =
Given that: g = 9.8 m/, radius of the earth is 6371000 m, mass of the earth is 5.972 × kg, then;
G =
= 1.670 ×
Answer:
Asteroids are objects made of clay and silicate that orbit the sun but are too small to be considered planets.
Most asteroids revolve around the sun in an orbit between those of Mars and Jupiter.
They form a wide band called the Asteroid belt.
Other asteroids have orbits that cross Earth’s orbit. These asteroids are called Earth-crossers.
Asteroids probably consist of matter that never agglomerated into a planet when the solar system was forming.
The comet’s core is composed of ice and dust.
Comets heat up and begin to change from a solid to a gas as they approach the sun.
The matter surrounding a comet’s core is vaporized and forms a very bright halo of ice or dust not sure, and an enormous cloud of dust or gasses not sure envelopes the head of the comet.
<span>a) 1960 m
b) 960 m
Assumptions.
1. Ignore air resistance.
2. Gravity is 9.80 m/s^2
For the situation where the balloon was stationary, the equation for the distance the bottle fell is
d = 1/2 AT^2
d = 1/2 9.80 m/s^2 (20s)^2
d = 4.9 m/s^2 * 400 s^2
d = 4.9 * 400 m
d = 1960 m
For situation b, the equation is quite similar except we need to account for the initial velocity of the bottle. We can either assume that the acceleration for gravity is negative, or that the initial velocity is negative. We just need to make certain that the two effects (falling due to acceleration from gravity) and (climbing due to initial acceleration) counteract each other. So the formula becomes
d = 1/2 9.80 m/s^2 (20s)^2 - 50 m/s * T
d = 1/2 9.80 m/s^2 (20s)^2 - 50m/s *20s
d = 4.9 m/s^2 * 400 s^2 - 1000 m
d = 4.9 * 400 m - 1000 m
d = 1960 m - 1000 m
d = 960 m</span>