Do magnets have to touch each other in order to experience a magnetic force? explain

Which two objects have the greatest gravitational force acting between them

Point charges q1 = 51 µc and q2 = −27 µc are placed 1.0 m apart, with q2 on the right. what is the force (in n) on a third charge q3 = 19 µc placed midway between q1 and q2? (assume the positive direction is to the right. indicate the direction with the sign of your answer.)

An object dropped from cliff falls with a constant acceleration of 10 metre per second square find its speed of two seconds after it was dropped