Which statements describe the motion of a planet according to Kepler’s second law? Check all that apply. The speed of a planet varies as it moves in its orbit.
The speed of a planet is constant as it moves in its orbit.
A planet travels the same distance along its orbit in equal units of time.
A planet sweeps out an equal area in equal units of time.
A planet’s orbit is a circle centered on the Sun.
A planet’s orbit is an ellipse with the Sun at one focus.

Ablock of mass m = 2.5 kg is attached to a spring with spring constant k = 790 n/m. it is initially at rest on an inclined plane that is at an angle of 28 degrees with respect to the horizontal, and the coefficient of kinetic friction between the block and the plane is k = 0.14. in the initial position, where the spring is compressed by a distance of a = 0.18 m, the mass is at its lowest position and the spring is compressed the maximum amount. take the initial gravitational energy of the block as zero. b) if the spring pushes the block up the incline, what distance, l, in meters will the block travel before coming to rest? the spring remains attached to both the block and the fixed wall throughout its motion.

10 newton object is placed 3 meters from the fulcrum. at what distance on the other side would you need to place a 15 newton object to balance the lever? show your work!

Considering only the earth's rotation, determine how much later the asteroid would have had to arrive to put the explosion above helsinki at longitude 25˚ e? this would have obliterated the city.