When you skid to a stop on your bike, you can significantly heat the small patch of tire that rubs against the road surface. Suppose a person skids to a stop by hitting the brake on his back tire, which supports half the 80 kgkg combined mass of the bike and rider, leaving a skid mark that is 40 cmcm long. Assume a coefficient of kinetic friction of 0.80. How much thermal energy is deposited in the tire and the road surface?
Express your answer with the appropriate units.

If two students are running down the hall toward each other, trying to get to class, and they have the same mass and acceleration, what will happen when they collide? will their forces cancel out or will each one experience a reaction?

Athin nonconducting rod with a uniform distribution of positive charge q is bent into a circle of radius r. the central perpendicular axis through the ring is a z-axis, with the origin at the center of the ring. a) what is the magnitude of the electric field due to the rod at z = 0? n/c (b) what is the magnitude of the electric field due to the rod at z = infinity? n/c (c) in terms of r, at what positive value of z is that magnitude maximum? r (d) if r = 4.00 cm and q = 9.00 µc, what is the maximum magnitude? n/c

Identify the type of heat transfer occurring when chocolate melts in your hand