Students are asked to design an experiment about Newton's 2nd Law. One student
decides to roll a marble down a few ramp into a
pile of sand to measure the force impact.
Which variable should she manipulate to
best exemplify the relationship explained by
this law?

How to tell if a molecule is polar or nonpolar with electronegativity

Ablock of mass m = 2.5 kg is attached to a spring with spring constant k = 740 n/m. it is initially at rest on an inclined plane that is at an angle of theta= 26 with respect to the horizontal, and the coefficient of kinetic friction between the block and the plane is uk = 0.17. in the initial position, where the spring is compressed by a distance of d = 0.16 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. the block's initial mechanical energy is 9.472 j.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.

Suppose two stars are located in region a of the h-r diagram shown in the figure below. star c appears much dimmer than star y as seen from earth. which star can be inferred to be nearer to earth and how do you know?