The vector sum of forces acting on a non-accelerating object equals zero.
equation form: ΣF = 0
Kepler derived his three laws of planetary motion entirely from
observations of the planets and their motions in the sky.
Newton published his law of universal gravitation almost a hundred
years later. Using some calculus and some analytic geometry, which
any serious sophomore in an engineering college should be able to do,
it can be shown that IF Newton's law of gravitation is correct, then it MUST
lead to Kepler's laws. Gravity, as Newton described it, must make the planets
in their orbits behave exactly as they do.
This demonstration is a tremendous boost for the work of both Kepler
and Newton.
Answer :First part is what you learned so write what you learned then the other parts is The evidence that the universe is expanding comes with something called the red shift of light. Light travels to Earth from other galaxies. As the light from that galaxy gets closer to Earth, the distance between Earth and the galaxy increases, which causes the wavelength of that light to get longer.
Explanation:
Draw a right triangle so that its hypotenuse is 600 ft. The adjacent side is below the vertical, and it makes an angle of 75° with the hypotenuse.
Let h = height of the right triangle.
By definition,
sin75° = h/600
h = 600*sin75° = 579.555 = 580 ft (nearest ft)
Answer: 580 ft (nearest foot)
Answer:
b. Static > sliding > rolling friction.
Explanation:
Static friction is greater than sliding friction. It takes more force to get an object to start sliding than to keep it sliding.
Sliding friction is greater than rolling friction. There are fewer points of contact for a round surface compared to a flat one.
