CONTACT FORCES
The force applied by a magnet on an iron nail.
The force applied by a student on a door to open it.
NON-CONTACT FORCES
The force applied by an electromagnet on a wire.
The force applied by the planets on each other.
Which statement best explains why the table is incorrect?
A. Magnetic force is a force acting at a distance
B. The student applies a non-contact force on the door
C. Electromagnets use contact force
D. Gravitational force acts between planets only when they are in contact.