Can someone check my answers ? ?

which of these is true about a bar magnet?

its north pole tends to point south.

its poles can be separated into two isolated poles.

its poles attract or repel because of their net electric charge.

> it attracts unmagnetized iron objects by making them magnetically polarized.

Abicycle slows down when the rider applies the brakes. what type of energy transformation is involved in this example? a. kinetic energy into heat energy b. heat energy into potential energy c. potential energy into kinetic energy d. kinetic energy into mechanical energy

Aball is thrown from the top of a building with an initial velocity of 21.9 m/s straight upward, at an initial height of 51.6 m above the ground. the ball just misses the edge of the roof on its way down, as shown in the figure. (a) determine the time needed for the ball to reach its maximum height. (b) determine the maximum height. (c) determine the time needed for the ball to return to the height from which it was thrown, and the velocity of the ball at that instant. (d) determine the time needed for the ball to reach the ground. (e) determine the velocity and position of the ball at t = 5.35 s.

How does the strength of the electrostatic force between an electron and a proton compare to the strength of the gravitational force between them?